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Microstructure Analysis of TC4/Al 6063/Al 7075 Explosive Welded Composite Plate via Multi-scale Simulation and Experiment 被引量:1
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作者 Zhou Jianan Luo Ning +3 位作者 Liang Hanliang Chen Jinhua Liu Zhibing Zhou Xiaohong 《稀有金属材料与工程》 北大核心 2025年第1期27-38,共12页
Because of the challenge of compounding lightweight,high-strength Ti/Al alloys due to their considerable disparity in properties,Al 6063 as intermediate layer was proposed to fabricate TC4/Al 6063/Al 7075 three-layer ... Because of the challenge of compounding lightweight,high-strength Ti/Al alloys due to their considerable disparity in properties,Al 6063 as intermediate layer was proposed to fabricate TC4/Al 6063/Al 7075 three-layer composite plate by explosive welding.The microscopic properties of each bonding interface were elucidated through field emission scanning electron microscope and electron backscattered diffraction(EBSD).A methodology combining finite element method-smoothed particle hydrodynamics(FEM-SPH)and molecular dynamics(MD)was proposed for the analysis of the forming and evolution characteristics of explosive welding interfaces at multi-scale.The results demonstrate that the bonding interface morphologies of TC4/Al 6063 and Al 6063/Al 7075 exhibit a flat and wavy configuration,without discernible defects or cracks.The phenomenon of grain refinement is observed in the vicinity of the two bonding interfaces.Furthermore,the degree of plastic deformation of TC4 and Al 7075 is more pronounced than that of Al 6063 in the intermediate layer.The interface morphology characteristics obtained by FEM-SPH simulation exhibit a high degree of similarity to the experimental results.MD simulations reveal that the diffusion of interfacial elements predominantly occurs during the unloading phase,and the simulated thickness of interfacial diffusion aligns well with experimental outcomes.The introduction of intermediate layer in the explosive welding process can effectively produce high-quality titanium/aluminum alloy composite plates.Furthermore,this approach offers a multi-scale simulation strategy for the study of explosive welding bonding interfaces. 展开更多
关键词 TC4/Al 6063/Al 7075 composite plate explosive welding microstructure analysis multi-scale simulation
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A multi-scale and multi-mechanism coupled model for carbon isotope fractionation of methane during shale gas production 被引量:1
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作者 Jun Wang Fang-Wen Chen +4 位作者 Wen-Biao Li Shuang-Fang Lu Sheng-Xian Zhao Yong-Yang Liu Zi-Yi Wang 《Petroleum Science》 2025年第7期2719-2746,共28页
Prediction of production decline and evaluation of the adsorbed/free gas ratio are critical for determining the lifespan and production status of shale gas wells.Traditional production prediction methods have some sho... Prediction of production decline and evaluation of the adsorbed/free gas ratio are critical for determining the lifespan and production status of shale gas wells.Traditional production prediction methods have some shortcomings because of the low permeability and tightness of shale,complex gas flow behavior of multi-scale gas transport regions and multiple gas transport mechanism superpositions,and complex and variable production regimes of shale gas wells.Recent research has demonstrated the existence of a multi-stage isotope fractionation phenomenon during shale gas production,with the fractionation characteristics of each stage associated with the pore structure,gas in place(GIP),adsorption/desorption,and gas production process.This study presents a new approach for estimating shale gas well production and evaluating the adsorbed/free gas ratio throughout production using isotope fractionation techniques.A reservoir-scale carbon isotope fractionation(CIF)model applicable to the production process of shale gas wells was developed for the first time in this research.In contrast to the traditional model,this model improves production prediction accuracy by simultaneously fitting the gas production rate and δ^(13)C_(1) data and provides a new evaluation method of the adsorbed/free gas ratio during shale gas production.The results indicate that the diffusion and adsorption/desorption properties of rock,bottom-hole flowing pressure(BHP)of gas well,and multi-scale gas transport regions of the reservoir all affect isotope fractionation,with the diffusion and adsorption/desorption parameters of rock having the greatest effect on isotope fractionation being D∗/D,PL,VL,α,and others in that order.We effectively tested the universality of the four-stage isotope fractionation feature and revealed a unique isotope fractionation mechanism caused by the superimposed coupling of multi-scale gas transport regions during shale gas well production.Finally,we applied the established CIF model to a shale gas well in the Sichuan Basin,China,and calculated the estimated ultimate recovery(EUR)of the well to be 3.33×10^(8) m^(3);the adsorbed gas ratio during shale gas production was 1.65%,10.03%,and 23.44%in the first,fifth,and tenth years,respectively.The findings are significant for understanding the isotope fractionation mechanism during natural gas transport in complex systems and for formulating and optimizing unconventional natural gas development strategies. 展开更多
关键词 Shale gas Isotope fractionation multi-scale Production prediction Adsorbed/free gas ratio
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Influence of heavy reduction during solidification process of billets based on 3D reconstruction of dendrites 被引量:1
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作者 Yi Nian You-cheng Zong +3 位作者 Chao-jie Zhang Xin-yu Tang Jia-le Li Li-qiang Zhang 《Journal of Iron and Steel Research International》 2025年第6期1596-1611,共16页
The impact of heavy reduction on dendritic morphology was explored by combining experimental research and numerical simulation in metallurgy,including a detailed three-dimensional(3D)analysis and reconstruction of den... The impact of heavy reduction on dendritic morphology was explored by combining experimental research and numerical simulation in metallurgy,including a detailed three-dimensional(3D)analysis and reconstruction of dendritic solidification structures.Combining scanning electron microscopy and energy-dispersive scanning analysis and ANSYS simulation,the high-precision image processing software Mimics Research was utilized to conduct the extraction of dendritic morphologies.Reverse engineering software NX Imageware was employed for the 3D reconstruction of two-dimensional dendritic morphologies,restoring the dendritic characteristics in three-dimensional space.The results demonstrate that in a two-dimensional plane,dendrites connect with each other to form irregularly shaped“ring-like”structures.These dendrites have a thickness greater than 0.1 mm along the Z-axis direction,leading to the envelopment of molten steel by dendrites in a 3D space of at least 0.1 mm.This results in obstructed flow,confirming the“bridging”of dendrites in three-dimensional space,resulting in a tendency for central segregation.Dense and dispersed tiny dendrites,under the influence of heat flow direction,interconnect and continuously grow,gradually forming primary and secondary dendrites in three-dimensional space.After the completion of dendritic solidification and growth,these microdendrites appear dense and dispersed on the two-dimensional plane,providing the nuclei for the formation of new dendrites.When reduction occurs at a solid fraction of 0.46,there is a noticeable decrease in dendritic spacing,resulting in improved central segregation. 展开更多
关键词 SOLIDIFICATION Dendritic growth 3D reconstruction Heavy reduction Central segregation
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Occluded Gait Emotion Recognition Based on Multi-Scale Suppression Graph Convolutional Network
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作者 Yuxiang Zou Ning He +2 位作者 Jiwu Sun Xunrui Huang Wenhua Wang 《Computers, Materials & Continua》 SCIE EI 2025年第1期1255-1276,共22页
In recent years,gait-based emotion recognition has been widely applied in the field of computer vision.However,existing gait emotion recognition methods typically rely on complete human skeleton data,and their accurac... In recent years,gait-based emotion recognition has been widely applied in the field of computer vision.However,existing gait emotion recognition methods typically rely on complete human skeleton data,and their accuracy significantly declines when the data is occluded.To enhance the accuracy of gait emotion recognition under occlusion,this paper proposes a Multi-scale Suppression Graph ConvolutionalNetwork(MS-GCN).TheMS-GCN consists of three main components:Joint Interpolation Module(JI Moudle),Multi-scale Temporal Convolution Network(MS-TCN),and Suppression Graph Convolutional Network(SGCN).The JI Module completes the spatially occluded skeletal joints using the(K-Nearest Neighbors)KNN interpolation method.The MS-TCN employs convolutional kernels of various sizes to comprehensively capture the emotional information embedded in the gait,compensating for the temporal occlusion of gait information.The SGCN extracts more non-prominent human gait features by suppressing the extraction of key body part features,thereby reducing the negative impact of occlusion on emotion recognition results.The proposed method is evaluated on two comprehensive datasets:Emotion-Gait,containing 4227 real gaits from sources like BML,ICT-Pollick,and ELMD,and 1000 synthetic gaits generated using STEP-Gen technology,and ELMB,consisting of 3924 gaits,with 1835 labeled with emotions such as“Happy,”“Sad,”“Angry,”and“Neutral.”On the standard datasets Emotion-Gait and ELMB,the proposed method achieved accuracies of 0.900 and 0.896,respectively,attaining performance comparable to other state-ofthe-artmethods.Furthermore,on occlusion datasets,the proposedmethod significantly mitigates the performance degradation caused by occlusion compared to other methods,the accuracy is significantly higher than that of other methods. 展开更多
关键词 KNN interpolation multi-scale temporal convolution suppression graph convolutional network gait emotion recognition human skeleton
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A Generative Model-Based Network Framework for Ecological Data Reconstruction
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作者 Shuqiao Liu Zhao Zhang +1 位作者 Hongyan Zhou Xuebo Chen 《Computers, Materials & Continua》 SCIE EI 2025年第1期929-948,共20页
This study examines the effectiveness of artificial intelligence techniques in generating high-quality environmental data for species introductory site selection systems.Combining Strengths,Weaknesses,Opportunities,Th... This study examines the effectiveness of artificial intelligence techniques in generating high-quality environmental data for species introductory site selection systems.Combining Strengths,Weaknesses,Opportunities,Threats(SWOT)analysis data with Variation Autoencoder(VAE)and Generative AdversarialNetwork(GAN)the network framework model(SAE-GAN),is proposed for environmental data reconstruction.The model combines two popular generative models,GAN and VAE,to generate features conditional on categorical data embedding after SWOT Analysis.The model is capable of generating features that resemble real feature distributions and adding sample factors to more accurately track individual sample data.Reconstructed data is used to retain more semantic information to generate features.The model was applied to species in Southern California,USA,citing SWOT analysis data to train the model.Experiments show that the model is capable of integrating data from more comprehensive analyses than traditional methods and generating high-quality reconstructed data from them,effectively solving the problem of insufficient data collection in development environments.The model is further validated by the Technique for Order Preference by Similarity to an Ideal Solution(TOPSIS)classification assessment commonly used in the environmental data domain.This study provides a reliable and rich source of training data for species introduction site selection systems and makes a significant contribution to ecological and sustainable development. 展开更多
关键词 Convolutional Neural Network(CNN) VAE GAN TOPSIS data reconstruction
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Deciphering Water Oxidation Catalysts:The Dominant Role of Surface Chemistry over Reconstruction Degree in Activity Promotion
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作者 Li An Jianyi Li +7 位作者 Yuanmiao Sun Jiamin Zhu Justin Zhu Yeow Seow Hong Zhang Nan Zhang Pinxian Xi Zhichuan J.Xu Chun‑Hua Yan 《Nano-Micro Letters》 SCIE EI CAS 2025年第3期340-354,共15页
Water splitting hinges crucially on the availability of electrocatalysts for the oxygen evolution reaction.The surface reconstruction has been widely observed in perovskite catalysts,and the reconstruction degree has ... Water splitting hinges crucially on the availability of electrocatalysts for the oxygen evolution reaction.The surface reconstruction has been widely observed in perovskite catalysts,and the reconstruction degree has been often correlated with the activity enhancement.Here,a systematic study on the roles of Fe substitution in activation of perovskite LaNiO_(3)is reported.The substituting Fe content influences both current change tendency and surface reconstruction degree.LaNi_(0.9)Fe_(0.1)O_(3)is found exhibiting a volcano-peak intrinsic activity in both pristine and reconstructed among all substituted perovskites in the LaNi_(1-x)Fe_(x)O_(3)(x=0.00,0.10,0.25,0.50,0.75,1.00)series.The reconstructed LaNi_(0.9)Fe_(0.1)O_(3)shows a higher intrinsic activity than most reported NiFe-based catalysts.Besides,density functional theory calculations reveal that Fe substitution can lower the O 2p level,which thus stabilize lattice oxygen in LaNi0.9Fe0.1O3 and ensure its long-term stability.Furthermore,it is vital interesting that activity of the reconstructed catalysts relied more on the surface chemistry rather than the reconstruction degree.The effect of Fe on the degree of surface reconstruction of the perovskite is decoupled from that on its activity enhancement after surface reconstruction.This finding showcases the importance to customize the surface chemistry of reconstructed catalysts for water oxidation. 展开更多
关键词 Oxygen evolution reaction Perovskite oxides DOPING Activation and reconstruction
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Navigating medial patellotibial ligament reconstruction:Clinical perspectives and surgical strategies
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作者 Juan Pablo Zicaro Ignacio Garcia-Mansilla 《World Journal of Clinical Cases》 SCIE 2025年第1期6-10,共5页
The surgical approach for patellar instability usually refers to reconstruction of the medial patellofemoral ligament associated with an osteotomy of the tibial tuberosity or a trochleoplasty when required.The medial ... The surgical approach for patellar instability usually refers to reconstruction of the medial patellofemoral ligament associated with an osteotomy of the tibial tuberosity or a trochleoplasty when required.The medial patellotibial ligament and the medial patellomeniscal ligament are secondary stabilizers of the patella.Despite this,both the medial patellotibial and patellofemoral ligaments aid in patellar rotation and tilt when the knee is flexed beyond 45°.The medial patellotibial ligament plays a particularly important role in the final stages of stretching in extension and between 40 degrees to 90 degrees of flexion.The clinical relevance and surgical indications for medial patellotibial ligament reconstruction associated with medial patellofemoral ligament reconstruction are still controversial.This editorial explores the surgical indications and clinical results for medial patellotibial ligament reconstruction to improve readers’understanding of this technique,especially because reported clinical outcomes have remained sparse. 展开更多
关键词 Medial patellotibial ligament Patellar instability reconstruction SURGICAL
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BDMFuse:Multi-scale network fusion for infrared and visible images based on base and detail features
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作者 SI Hai-Ping ZHAO Wen-Rui +4 位作者 LI Ting-Ting LI Fei-Tao Fernando Bacao SUN Chang-Xia LI Yan-Ling 《红外与毫米波学报》 北大核心 2025年第2期289-298,共10页
The fusion of infrared and visible images should emphasize the salient targets in the infrared image while preserving the textural details of the visible images.To meet these requirements,an autoencoder-based method f... The fusion of infrared and visible images should emphasize the salient targets in the infrared image while preserving the textural details of the visible images.To meet these requirements,an autoencoder-based method for infrared and visible image fusion is proposed.The encoder designed according to the optimization objective consists of a base encoder and a detail encoder,which is used to extract low-frequency and high-frequency information from the image.This extraction may lead to some information not being captured,so a compensation encoder is proposed to supplement the missing information.Multi-scale decomposition is also employed to extract image features more comprehensively.The decoder combines low-frequency,high-frequency and supplementary information to obtain multi-scale features.Subsequently,the attention strategy and fusion module are introduced to perform multi-scale fusion for image reconstruction.Experimental results on three datasets show that the fused images generated by this network effectively retain salient targets while being more consistent with human visual perception. 展开更多
关键词 infrared image visible image image fusion encoder-decoder multi-scale features
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Exploration of Gas‑Dependent Self‑Adaptive Reconstruction Behavior of Cu_(2)O for Electrochemical CO_(2) Conversion to Multi‑Carbon Products
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作者 Chaoran Zhang Yichuan Gu +7 位作者 Qu Jiang Ziyang Sheng Ruohan Feng Sihong Wang Haoyue Zhang Qianqing Xu Zijian Yuan Fang Song 《Nano-Micro Letters》 SCIE EI CAS 2025年第3期280-296,共17页
Structural reconstruction of electrocatalysts plays a pivotal role in catalytic performances for CO_(2)reduction reaction(CO_(2)RR),whereas the behavior is by far superficially understood.Here,we report that CO_(2)acc... Structural reconstruction of electrocatalysts plays a pivotal role in catalytic performances for CO_(2)reduction reaction(CO_(2)RR),whereas the behavior is by far superficially understood.Here,we report that CO_(2)accessibility results in a universal self-adaptive structural reconstruction from Cu_(2)O to Cu@CuxO composites,ending with feeding gas-dependent microstructures and catalytic performances.The CO_(2)-rich atmosphere favors reconstruction for CO_(2)RR,whereas the CO_(2)-deficient one prefers that for hydrogen evolution reaction.With the assistance of spectroscopic analysis and theoretical calculations,we uncover a CO_(2)-induced passivation behavior by identifying a reductionresistant but catalytic active Cu(I)-rich amorphous layer stabilized by*CO intermediates.Additionally,we find extra CO production is indispensable for the robust production of C2H4.An inverse correlation between durability and FECO/FEC2H4 is disclosed,suggesting that the selfstabilization process involving the absorption of*CO intermediates on Cu(I)sites is essential for durable electrolysis.Guided by this insight,we design hollow Cu_(2)O nanospheres for durable and selective CO_(2)RR electrolysis in producing C2H4.Our work recognizes the previously overlooked passivation reconstruction and self-stabilizing behavior and highlights the critical role of the local atmosphere in modulating reconstruction and catalytic processes. 展开更多
关键词 CO_(2)reduction reaction ELECTROCATALYSTS Cu_(2)O reconstruction Self-adaptive electrocatalysis
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A Nonlinear Multi-Scale Interaction Model for Atmospheric Blocking:A Tool for Exploring the Impact of Changing Climate on Mid-to-High Latitude Weather Extremes 被引量:1
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作者 Dehai LUO Wenqi ZHANG Binhe LUO 《Advances in Atmospheric Sciences》 2025年第10期2018-2035,共18页
A nonlinear multi-scale interaction(NMI)model was proposed and developed by the first author for nearly 30 years to represent the evolution of atmospheric blocking.In this review paper,we first review the creation and... A nonlinear multi-scale interaction(NMI)model was proposed and developed by the first author for nearly 30 years to represent the evolution of atmospheric blocking.In this review paper,we first review the creation and development of the NMI model and then emphasize that the NMI model represents a new tool for identifying the basic physics of how climate change influences mid-to-high latitude weather extremes.The building of the NMI model took place over three main periods.In the 1990s,a nonlinear Schr?dinger(NLS)equation model was presented to describe atmospheric blocking as a wave packet;however,it could not depict the lifetime(10-20 days)of atmospheric blocking.In the 2000s,we proposed an NMI model of atmospheric blocking in a uniform basic flow by making a scale-separation assumption and deriving an eddyforced NLS equation.This model succeeded in describing the life cycle of atmospheric blocking.In the 2020s,the NMI model was extended to include the impact of a changing climate mainly by altering the basic zonal winds and the magnitude of the meridional background potential vorticity gradient(PVy).Model results show that when PVy is smaller,blocking has a weaker dispersion and a stronger nonlinearity,so blocking can be more persistent and have a larger zonal scale and weaker eastward movement,thus favoring stronger weather extremes.However,when PVy is much smaller and below a critical threshold under much stronger winter Arctic warming of global warming,atmospheric blocking becomes locally less persistent and shows a much stronger westward movement,which acts to inhibit local cold extremes.Such a case does not happen in summer under global warming because PVy fails to fall below the critical threshold.Thus,our theory indicates that global warming can render summer-blocking anticyclones and mid-to-high latitude heatwaves more persistent,intense,and widespread. 展开更多
关键词 nonlinear Schrödinger equation nonlinear multi-scale interaction model of atmospheric blocking meridional background potential vorticity gradient climate change mid-to-high latitude weather extremes
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Image Super-Resolution Reconstruction Model Based on SRGAN
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作者 LU Xin-ya CHEN Jia-yi +1 位作者 SI Zhan-jun ZHANG Ying-xue 《印刷与数字媒体技术研究》 北大核心 2025年第5期21-28,共8页
Image super-resolution reconstruction technology is currently widely used in medical imaging,video surveillance,and industrial quality inspection.It not only enhances image quality but also improves details and visual... Image super-resolution reconstruction technology is currently widely used in medical imaging,video surveillance,and industrial quality inspection.It not only enhances image quality but also improves details and visual perception,significantly increasing the utility of low-resolution images.In this study,an improved image superresolution reconstruction model based on Generative Adversarial Networks(SRGAN)was proposed.This model introduced a channel and spatial attention mechanism(CSAB)in the generator,allowing it to effectively leverage the information from the input image to enhance feature representations and capture important details.The discriminator was designed with an improved PatchGAN architecture,which more accurately captured local details and texture information of the image.With these enhanced generator and discriminator architectures and an optimized loss function design,this method demonstrated superior performance in image quality assessment metrics.Experimental results showed that this model outperforms traditional methods,presenting more detailed and realistic image details in the visual effects. 展开更多
关键词 Image super-resolution reconstruction Generative Adversarial Networks CSAB PatchGAN architecture
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Multi-target neural circuit reconstruction and enhancement in spinal cord injury 被引量:1
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作者 Lingyun Cao Siyun Chen +2 位作者 Shuping Wang Ya Zheng Dongsheng Xu 《Neural Regeneration Research》 2026年第3期957-971,共15页
After spinal cord injury,impairment of the sensorimotor circuit can lead to dysfunction in the motor,sensory,proprioceptive,and autonomic nervous systems.Functional recovery is often hindered by constraints on the tim... After spinal cord injury,impairment of the sensorimotor circuit can lead to dysfunction in the motor,sensory,proprioceptive,and autonomic nervous systems.Functional recovery is often hindered by constraints on the timing of interventions,combined with the limitations of current methods.To address these challenges,various techniques have been developed to aid in the repair and reconstruction of neural circuits at different stages of injury.Notably,neuromodulation has garnered considerable attention for its potential to enhance nerve regeneration,provide neuroprotection,restore neurons,and regulate the neural reorganization of circuits within the cerebral cortex and corticospinal tract.To improve the effectiveness of these interventions,the implementation of multitarget early interventional neuromodulation strategies,such as electrical and magnetic stimulation,is recommended to enhance functional recovery across different phases of nerve injury.This review concisely outlines the challenges encountered following spinal cord injury,synthesizes existing neurostimulation techniques while emphasizing neuroprotection,repair,and regeneration of impaired connections,and advocates for multi-targeted,task-oriented,and timely interventions. 展开更多
关键词 multi-targets nerve root magnetic stimulation neural circuit NEUROMODULATION peripheral nerve stimulation reconstruction spinal cord injury task-oriented training TIMING transcranial magnetic stimulation
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Hemorrhagic Cyclops Syndrome—A Cause of Recurrent Hemarthrosis after ACL Reconstruction: A Case Report
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作者 Wesson Pious A. Espiritu 《Open Journal of Orthopedics》 2025年第1期15-21,共7页
Cyclops lesion is a fibrous nodule on the tibial side of the knee and it is one of the common complications that arises after anterior cruciate ligament (ACL) reconstruction, causing loss of knee extension. A presenta... Cyclops lesion is a fibrous nodule on the tibial side of the knee and it is one of the common complications that arises after anterior cruciate ligament (ACL) reconstruction, causing loss of knee extension. A presentation dominated by recurrent hemarthrosis is a rare presentation of this lesion. In this case report, we have discussed about a male patient who presented with recurrent hemarthrosis and inability to extend the knee joint fully 8 months after ACL reconstruction. Cyclops lesion was identified by clinical examination and magnetic resonance imaging (MRI). Recurrence after initial excision of the lesion occurred and complete resolution happened during the second operation when cauterization was done. It is imperative that treatment should include coagulation of the vascularized stump to avoid any recurrence. 展开更多
关键词 Cyclops Syndrome HEMARTHROSIS ACL reconstruction Hemorrhagic Cyclops
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Infrared-NeRF:a low resolution thermal infrared light field 3D reconstruction method based on NeRF
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作者 HUANG Yi-Fan WANG Rui +2 位作者 DENG Li-Ming LI Jia-Jia LI Xi-Cai 《红外与毫米波学报》 北大核心 2025年第4期605-616,共12页
This article proposes a three-dimensional light field reconstruction method based on neural radiation field(NeRF)called Infrared NeRF for low resolution thermal infrared scenes.Based on the characteristics of the low ... This article proposes a three-dimensional light field reconstruction method based on neural radiation field(NeRF)called Infrared NeRF for low resolution thermal infrared scenes.Based on the characteristics of the low resolution thermal infrared imaging,various optimizations have been carried out to improve the speed and accuracy of thermal infrared 3D reconstruction.Firstly,inspired by Boltzmann's law of thermal radiation,distance is incorporated into the NeRF model for the first time,resulting in a nonlinear propagation of a single ray and a more accurate description of the physical property that infrared radiation intensity decreases with increasing distance.Secondly,in terms of improving inference speed,based on the phenomenon of high and low frequency distribution of foreground and background in infrared images,a multi ray non-uniform light synthesis strategy is proposed to make the model pay more attention to foreground objects in the scene,reduce the distribution of light in the background,and significantly reduce training time without reducing accuracy.In addition,compared to visible light scenes,infrared images only have a single channel,so fewer network parameters are required.Experiments using the same training data and data filtering method showed that,compared to the original NeRF,the improved network achieved an average improvement of 13.8%and 4.62%in PSNR and SSIM,respectively,while an average decreases of 46%in LPIPS.And thanks to the optimization of network layers and data filtering methods,training only takes about 25%of the original method's time to achieve convergence.Finally,for scenes with weak backgrounds,this article improves the inference speed of the model by 4-6 times compared to the original NeRF by limiting the query interval of the model. 展开更多
关键词 neural radiation field 3D reconstruction thermal infrared NeRF foreground segmentation low resolution
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Non-Neural 3D Nasal Reconstruction:A Sparse Landmark Algorithmic Approach for Medical Applications
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作者 Nguyen Khac Toan Ho Nguyen Anh Tuan Nguyen Truong Thinh 《Computer Modeling in Engineering & Sciences》 2025年第5期1273-1295,共23页
This paper presents a novel method for reconstructing a highly accurate 3D nose model of the human from 2D images and pre-marked landmarks based on algorithmic methods.The study focuses on the reconstruction of a 3D n... This paper presents a novel method for reconstructing a highly accurate 3D nose model of the human from 2D images and pre-marked landmarks based on algorithmic methods.The study focuses on the reconstruction of a 3D nose model tailored for applications in healthcare and cosmetic surgery.The approach leverages advanced image processing techniques,3D Morphable Models(3DMM),and deformation techniques to overcome the limita-tions of deep learning models,particularly addressing the interpretability issues commonly encountered in medical applications.The proposed method estimates the 3D coordinates of landmark points using a 3D structure estimation algorithm.Sub-landmarks are extracted through image processing techniques and interpolation.The initial surface is generated using a 3DMM,though its accuracy remains limited.To enhance precision,deformation techniques are applied,utilizing the coordinates of 76 identified landmarks and sub-landmarks.The resulting 3D nose model is constructed based on algorithmic methods and pre-marked landmarks.Evaluation of the 3D model is conducted by comparing landmark distances and shape similarity with expert-determined ground truth on 30 Vietnamese volunteers aged 18 to 47,all of whom were either preparing for or required nasal surgery.Experimental results demonstrate a strong agreement between the reconstructed 3D model and the ground truth.The method achieved a mean landmark distance error of 0.631 mm and a shape error of 1.738 mm,demonstrating its potential for medical applications. 展开更多
关键词 Nose reconstruction 3D reconstruction medical applications algorithmic reconstruction enhanced 3D model
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The Role of Multi-scale Integrated Hierarchical Intervention in Preventing Psychological Crises among College Students
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作者 XIONG Jun ZHAO Xiaoqing +3 位作者 SHUAI Yixin FENG Yuqi ZHUGE Junzhe LUO Jiaming 《贵州大学学报(自然科学版)》 2025年第4期18-25,共8页
Mental health problems and potential psychological crises affect the healthy growth and learning performance of college students.Effective and suitable prevention of psychological crises among college students is a co... Mental health problems and potential psychological crises affect the healthy growth and learning performance of college students.Effective and suitable prevention of psychological crises among college students is a continuous challenge university managers face.To explore a method of preventing psychological crises among college students,we measured 38661 students by using SCL-90(symptom check list-90)and screened out 5790 students with positive results.Then,we measured 33188 students by using PHQ-9(patient health questionnaire-9)and screened out 603 students with suicidal ideation or behavior;we interviewed 392 students by using GAQ(growth adversity questionnaire).The number of students who had positive results at both phases is 155.As a result,we obtained a data set(N=76)by integrating the students who tested positive on the PHQ-9(i.e.total score≥20)with those who completed the PHQ-9 and GAQ.In addition,we obtained a data set(N=50)by excluding the cases in which the GAQ score is 0.With regard to QCA(qualitative comparative analysis)results,the data set(N=76)exhibits 5 constellations of solutions with a coverage rate greater than 0.7,and the first eight indicators of the PHQ-9 constitute the explanatory variables in the combined solutions.About the data set(N=50),the combined solutions are extremely complicated and the explanatory variables encompass indicators from both the PHQ-9 and GAQ.All these mean that the multi-scale could more comprehensively reflect mental health states of college students,thus enhance the accuracy and effectiveness of the corresponding hierarchical intervention,and finally provide support for preventing psychological crises in universities. 展开更多
关键词 multi-scale hierarchical intervention preventing psychological crises
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Multi-scale modeling of the multi-phase flow in water electrolyzers for green hydrogen production
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作者 Lizhen Wu Qing Wang +2 位作者 Wenzhi Li Mingcong Tang Liang An 《Materials Reports(Energy)》 2025年第3期40-49,共10页
Water electrolyzers play a crucial role in green hydrogen production.However,their efficiency and scalability are often compromised by bubble dynamics across various scales,from nanoscale to macroscale components.This... Water electrolyzers play a crucial role in green hydrogen production.However,their efficiency and scalability are often compromised by bubble dynamics across various scales,from nanoscale to macroscale components.This review explores multi-scale modeling as a tool to visualize multi-phase flow and improve mass transport in water electrolyzers.At the nanoscale,molecular dynamics(MD)simulations reveal how electrode surface features and wettability influence nanobubble nucleation and stability.Moving to the mesoscale,models such as volume of fluid(VOF)and lattice Boltzmann method(LBM)shed light on bubble transport in porous transport layers(PTLs).These insights inform innovative designs,including gradient porosity and hydrophilic-hydrophobic patterning,aimed at minimizing gas saturation.At the macroscale,VOF simulations elucidate two-phase flow regimes within channels,showing how flow field geometry and wettability affect bubble discharging.Moreover,artificial intelligence(AI)-driven surrogate models expedite the optimization process,allowing for rapid exploration of structural parameters in channel-rib flow fields and porous flow field designs.By integrating these approaches,we can bridge theoretical insights with experimental validation,ultimately enhancing water electrolyzer performance,reducing costs,and advancing affordable,high-efficiency hydrogen production. 展开更多
关键词 Water electrolyzers Bubble dynamics multi-scale MULTI-PHASE MODELING
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Layered reconstruction framework for longitudinal segmented electromagnetic calorimeter
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作者 Jia-Le Fei Ao Yuan +2 位作者 Ke Wei Liang Sun Ji-Ke Wang 《Nuclear Science and Techniques》 2025年第9期43-58,共16页
In future high-energy physics experiments,the electromagnetic calorimeter(ECAL)should operate with an exceptionally high luminosity.An ECAL featuring a layered readout in the longitudinal direction and precise time-st... In future high-energy physics experiments,the electromagnetic calorimeter(ECAL)should operate with an exceptionally high luminosity.An ECAL featuring a layered readout in the longitudinal direction and precise time-stamped information offers a multidimensional view,thereby enriching our understanding of the showering process of electromagnetic particles in high-luminosity environments.This was used as the baseline design for several new experiments,including the planned upgrades of the current running experiments.Reconstructing and matching multidimensional information across different layers poses new challenges for the effective utilization of layered data.This study introduced a novel layered reconstruction framework for ECAL with a layered readout information structure and developed a corresponding layered clustering algorithm.This expands the concept of clusters from a plane to multiple layers.Additionally,this study presents the corresponding layered cluster correction methods,investigates the transverse shower profile utilized for overlapping cluster splitting,and develops a layered mergedπ^(0)reconstruction algorithm based on this framework.By incorporating energy and time information into 3-dimensions,this framework provides a suitable software platform for preliminary research on longitudinally segmented ECAL and new perspectives in physics analyses.Furthermore,using the PicoCal in LHCb Upgrade II as a concrete example,the performance of the framework was preliminarily evaluated using single photons andπ^(0)particles from the neutral B^(0)meson decay B^(0)→π^(+)π^(-)π^(0)as benchmarks.The results demonstrate that,compared to the unlayered framework,utilizing this framework for longitudinally segmented ECAL significantly enhances the position resolution and the ability to split overlapping clusters,thereby improving the reconstruction resolution and efficiency for photons andπ^(0)s. 展开更多
关键词 Electromagnetic calorimeter Layered reconstruction Transverse shower profile Mergedπ^(0)reconstruction
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Multi-Scale Feature Fusion Network for Accurate Detection of Cervical Abnormal Cells
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作者 Chuanyun Xu Die Hu +3 位作者 Yang Zhang Shuaiye Huang Yisha Sun Gang Li 《Computers, Materials & Continua》 2025年第4期559-574,共16页
Detecting abnormal cervical cells is crucial for early identification and timely treatment of cervical cancer.However,this task is challenging due to the morphological similarities between abnormal and normal cells an... Detecting abnormal cervical cells is crucial for early identification and timely treatment of cervical cancer.However,this task is challenging due to the morphological similarities between abnormal and normal cells and the significant variations in cell size.Pathologists often refer to surrounding cells to identify abnormalities.To emulate this slide examination behavior,this study proposes a Multi-Scale Feature Fusion Network(MSFF-Net)for detecting cervical abnormal cells.MSFF-Net employs a Cross-Scale Pooling Model(CSPM)to effectively capture diverse features and contextual information,ranging from local details to the overall structure.Additionally,a Multi-Scale Fusion Attention(MSFA)module is introduced to mitigate the impact of cell size variations by adaptively fusing local and global information at different scales.To handle the complex environment of cervical cell images,such as cell adhesion and overlapping,the Inner-CIoU loss function is utilized to more precisely measure the overlap between bounding boxes,thereby improving detection accuracy in such scenarios.Experimental results on the Comparison detector dataset demonstrate that MSFF-Net achieves a mean average precision(mAP)of 63.2%,outperforming state-of-the-art methods while maintaining a relatively small number of parameters(26.8 M).This study highlights the effectiveness of multi-scale feature fusion in enhancing the detection of cervical abnormal cells,contributing to more accurate and efficient cervical cancer screening. 展开更多
关键词 Cervical abnormal cells image detection multi-scale feature fusion contextual information
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Magnamosis for rectal reconstruction in canines
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作者 Shi-Qi Liu Hong-Ke Zhang +3 位作者 Yi Lv Xiang-Hua Xu Yu-Feng Li Dong-Wen Quan 《World Journal of Gastrointestinal Surgery》 2025年第2期227-236,共10页
BACKGROUND The magnamosis,a minimal invasive,suture-free procedure,has been used for digestive tract or vessel reconstruction,such as gastrointestinal anastomosis,bilioenteric anastomosis,and coronary artery bypass.Al... BACKGROUND The magnamosis,a minimal invasive,suture-free procedure,has been used for digestive tract or vessel reconstruction,such as gastrointestinal anastomosis,bilioenteric anastomosis,and coronary artery bypass.Although some case reports have demonstrated the potential of magnamosis for the treatment of congenital rectal atresia(RA),they cannot provide strong evidence for its widespread application.AIM To assess the feasibility and safety of magnamosis in treating RA in dogs as compared to suturing anastomosis.The findings of this study can be beneficial in guiding the clinical application of magnamosis.METHODS Thirty-six dogs were randomly assigned to the magnamosis group(n=18)and the suturing anastomosis group(n=18).The rectum was freed laparoscopically in all dogs.In the magnamosis group,rectal anastomosis was performed using a pair of magnetic rings,while the suturing anastomosis group underwent a straight-sighted end-to-end rectal anastomosis with 4-0 absorbable sutures.The anastomosis time was recorded,and abdominal plain film examination was performed to locate the magnets until they were expelled postoperatively.Specimens of the anastomosis were evaluated at one month,three months,and six months after surgery.RESULTS The mean time for rectal anastomosis was significantly shorter in the magnamosis group(12.22±2.78 minutes)than the suturing anastomosis group(18.11±1.68 minutes).There was one incidence of anastomotic bleeding in the suturing anastomosis group,whereas no complication was recorded in the magnamosis group.The magnets were discharged post-surgery in 7.17±1.30 days in all the dogs.The histopathological examination revealed a smoother healing of anastomotic mucosa in the magnamosis group as compared to that in the suturing anastomosis group.Moreover,the fiber alignment was also more natural in the magnamosis group with minimal inflammation.CONCLUSION Rectal reconstruction using magnamosis is a feasible,safe,and effective alternative to suturing anastomosis in dogs,with the added benefit of faster and more natural healing of the anastomosis. 展开更多
关键词 Rectal reconstruction CANINES Magnamosis DOGS
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