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利用Science Slides插件制作中学生物学教学课件——以“基因的本质”为例
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作者 卜倩 窦玉敏 +1 位作者 王功伍 韩宁 《中学课程资源》 2025年第4期54-59,共6页
中学生物学知识多是对生物体内部作用机理的探究,是人用肉眼不能直观获得和感知的,对于一些抽象的概念,学生是难以理解的。以“基因的本质”为例,介绍Science Slides插件在生物学教学中的应用,详细阐述运用Science Slides插件制作中学... 中学生物学知识多是对生物体内部作用机理的探究,是人用肉眼不能直观获得和感知的,对于一些抽象的概念,学生是难以理解的。以“基因的本质”为例,介绍Science Slides插件在生物学教学中的应用,详细阐述运用Science Slides插件制作中学生物学教学课件的方法,使抽象知识可视化,突破教学重、难点,为中学生物学教学课件的制作提供借鉴。 展开更多
关键词 中学生物学 Science slides 课件制作 抽象概念
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先天性气管狭窄患儿行改良Slide手术的气道护理
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作者 杨贻 唐晓敏 +1 位作者 诸纪华 谢春露 《护理与康复》 2025年第4期75-77,共3页
总结1例先天性气管狭窄患儿行改良Slide手术的气道护理经验。护理要点为做好术前呼吸道准备;术后行序贯氧疗,降低呼吸道感染概率;做好目标指导的镇静镇痛策略,为气道良好愈合提供条件;调整术后体位,促进气道愈合;采取个体化抗感染治疗,... 总结1例先天性气管狭窄患儿行改良Slide手术的气道护理经验。护理要点为做好术前呼吸道准备;术后行序贯氧疗,降低呼吸道感染概率;做好目标指导的镇静镇痛策略,为气道良好愈合提供条件;调整术后体位,促进气道愈合;采取个体化抗感染治疗,保持呼吸道正常微生态。本例患儿经过18 d治疗及护理,康复出院。随访3个月,患儿恢复良好。 展开更多
关键词 先天性气管狭窄 改良slide手术 “O”型气管环 护理
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Shear strength and permeability in the sliding zone soil of reservoir landslides:Insights into the seepage-shear coupling effect 被引量:1
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作者 Qianyun Wang Huiming Tang +3 位作者 Pengju An Kun Fang Biying Zhou Xinping Zhang 《Journal of Rock Mechanics and Geotechnical Engineering》 2025年第4期2031-2040,共10页
The strength of the sliding zone soil determines the stability of reservoir landslides.Fluctuations in water levels cause a change in the seepage field,which serves as both the external hydrogeological environment and... The strength of the sliding zone soil determines the stability of reservoir landslides.Fluctuations in water levels cause a change in the seepage field,which serves as both the external hydrogeological environment and the internal component of a landslide.Therefore,considering the strength changes of the sliding zone with seepage effects,they correspond with the actual hydrogeological circumstances.To investigate the shear behavior of sliding zone soil under various seepage pressures,24 samples were conducted by a self-developed apparatus to observe the shear strength and measure the permeability coefficients at different deformation stages.After seepage-shear tests,the composition of clay minerals and microscopic structure on the shear surface were analyzed through X-ray and scanning electron microscope(SEM)to understand the coupling effects of seepage on strength.The results revealed that the sliding zone soil exhibited strain-hardening without seepage pressure.However,the introduction of seepage caused a significant reduction in shear strength,resulting in strain-softening characterized by a three-stage process.Long-term seepage action softened clay particles and transported broken particles into effective seepage channels,causing continuous damage to the interior structure and reducing the permeability coefficient.Increased seepage pressure decreased the peak strength by disrupting occlusal and frictional forces between sliding zone soil particles,which carried away more clay particles,contributing to an overhead structure in the soil that raised the permeability coefficient and decreased residual strength.The internal friction angle was less sensitive to variations in seepage pressure than cohesion. 展开更多
关键词 Sliding zone soil Permeability coefficient Shear strength Seepage pressure Reservoir landslides
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Deep learning-based multi-task prediction of response to neoadjuvant chemotherapy using multiscale whole slide images in breast cancer:A multicenter study 被引量:1
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作者 Qin Wang Feng Zhao +19 位作者 Haicheng Zhang Tongpeng Chu Qi Wang Xipeng Pan Yuqian Chen Heng Zhou Tiantian Zheng Ziyin Li Fan Lin Haizhu Xie Heng Ma Lan Liu Lina Zhang Qin Li Weiwei Wang Yi Dai Ruijun Tang Jigang Wang Ping Yang Ning Mao 《Chinese Journal of Cancer Research》 2025年第1期28-47,共20页
Objective:Early predicting response before neoadjuvant chemotherapy(NAC)is crucial for personalized treatment plans for locally advanced breast cancer patients.We aim to develop a multi-task model using multiscale who... Objective:Early predicting response before neoadjuvant chemotherapy(NAC)is crucial for personalized treatment plans for locally advanced breast cancer patients.We aim to develop a multi-task model using multiscale whole slide images(WSIs)features to predict the response to breast cancer NAC more finely.Methods:This work collected 1,670 whole slide images for training and validation sets,internal testing sets,external testing sets,and prospective testing sets of the weakly-supervised deep learning-based multi-task model(DLMM)in predicting treatment response and pCR to NAC.Our approach models two-by-two feature interactions across scales by employing concatenate fusion of single-scale feature representations,and controls the expressiveness of each representation via a gating-based attention mechanism.Results:In the retrospective analysis,DLMM exhibited excellent predictive performance for the prediction of treatment response,with area under the receiver operating characteristic curves(AUCs)of 0.869[95%confidence interval(95%CI):0.806−0.933]in the internal testing set and 0.841(95%CI:0.814−0.867)in the external testing sets.For the pCR prediction task,DLMM reached AUCs of 0.865(95%CI:0.763−0.964)in the internal testing and 0.821(95%CI:0.763−0.878)in the pooled external testing set.In the prospective testing study,DLMM also demonstrated favorable predictive performance,with AUCs of 0.829(95%CI:0.754−0.903)and 0.821(95%CI:0.692−0.949)in treatment response and pCR prediction,respectively.DLMM significantly outperformed the baseline models in all testing sets(P<0.05).Heatmaps were employed to interpret the decision-making basis of the model.Furthermore,it was discovered that high DLMM scores were associated with immune-related pathways and cells in the microenvironment during biological basis exploration.Conclusions:The DLMM represents a valuable tool that aids clinicians in selecting personalized treatment strategies for breast cancer patients. 展开更多
关键词 Artificial intelligence breast cancer digital pathology whole slide images
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An Improved Slip Circle Method for Evaluating the Stability of Submarine Landslides under Wave Loading
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作者 Miaojun Sun Zhigang Shan +5 位作者 Changdong Li Jiaqing Zhou Qingbing Liu Xinji Zou Qilong Li Biwen Dong 《Journal of Earth Science》 2025年第3期1320-1326,共7页
0 INTRODUCTION Submarine slope slides refer to a geological process occurring on submarine slopes or continental margin slopes,where a large amount of sediment or rock layers on the slope lose stability and slide down... 0 INTRODUCTION Submarine slope slides refer to a geological process occurring on submarine slopes or continental margin slopes,where a large amount of sediment or rock layers on the slope lose stability and slide downward along the sliding surface(Kamran et al.,2023;Tong et al.,2023;Hampton et al.,1996). 展开更多
关键词 sliding surface kamran submarine slope slides submarine slopes wave loading geological process stability evaluation sediment rock layers continental margin slopeswhere
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Scratch & slide technique recanalization of long chronic iliac occlusion
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作者 Gianluca Rigatelli Dobrin Vassilev +3 位作者 Giuseppe Marchese Ervis Hiso Andrea Bertolini Marco Zuin 《Journal of Geriatric Cardiology》 2025年第7期690-694,共5页
Chronic long-segment iliac artery occlusion represents a relatively rare and particularly severe form of iliac artery disease,often associated with complex anatomical challenges.When symptomatic,these patients are typ... Chronic long-segment iliac artery occlusion represents a relatively rare and particularly severe form of iliac artery disease,often associated with complex anatomical challenges.When symptomatic,these patients are typically candidates for surgical revascularization. 展开更多
关键词 slide TECHNIQUE CHRONIC SCRATCH surgical revascularization ILIAC long segment iliac artery diseaseoften
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Mechanical Behavior of Sliding Zone Soil under Compression Considering Periodic Saturation-Drying:Example from a Giant Reservoir Landslide
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作者 Sha Lu Huiming Tang +2 位作者 Liangqing Wang Xuexue Su Bing Lyu 《Journal of Earth Science》 2025年第5期1936-1947,共12页
The reservoir landslide undergoes periodic saturation-drying cycles affected by reservoir fluctuation in hydropower project area,leading to the irreversible impact on the landslide materials.Sliding zone is the sheari... The reservoir landslide undergoes periodic saturation-drying cycles affected by reservoir fluctuation in hydropower project area,leading to the irreversible impact on the landslide materials.Sliding zone is the shearing part in formation of landslide and controls the further development of landslide.The mechanical behavior of sliding zone soil under compression is a crucial factor in the stability analysis in landslides.In this paper,the sliding zone soil from a giant landslide in the biggest hydropower project area,Three Gorges Reservoir Area,is taken as the research case.The particlesize distribution of the sliding zone soil from this landslide is studied and fractal dimension is adopted as representation.Periodic saturation-drying is introduced as the affecting factor on sliding zone soil properties.The triaxial compression test is conducted to reveal the mechanical behavior of the soil,including stress-strain behavior,elastic modulus,failure stress and strength parameters.These behavior of sliding zone soils with different fractal dimensions are studied under the effects of periodic saturation-drying cycles.The normalized stress-strain curves are displayed for further calculation.The data considering saturation-drying cycles are obtained and compared with the experimental results. 展开更多
关键词 periodic saturation-drying mechanical behavior sliding zone soil LANDslideS particle-size distribution stress-strain behavior engineering geology
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A method for optimizing and controlling rocking drillstringe-assisted slide drilling
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作者 Yabin Zhang Jian Lu +2 位作者 Binfeng Guo Xueying Wang Feifei Zhang 《Natural Gas Industry B》 2025年第1期77-87,共11页
Rocking the drillstring at the surface during slide drilling is a common method for reducing drag when drilling horizontal wells.However,the current methods for determining the parameters for rocking are insufficient,... Rocking the drillstring at the surface during slide drilling is a common method for reducing drag when drilling horizontal wells.However,the current methods for determining the parameters for rocking are insufficient,limiting the widespread use of this technology.In this study,the influence of rocking parameters on the friction-reduction effect was investigated using an axialetorsional dynamic model of the drillstring and an experimental apparatus for rocking-assisted slide drilling in a simulated horizontal well.The research shows that increasing the rocking speed is beneficial improving the friction-reduction effect,but there is a diminishing marginal effect.A method was proposed to optimize the rocking speed using the equivalent axial drag coefficienterocking speed curve.Under the influence of rocking,the downhole weight on bit(WOB)exhibits a sinusoidal-like variation,with the predominant frequency being twice the rocking frequency.The fluctuation amplitude of the WOB in the horizontal section has a linear relationship with the rocking-affected depth.Based on this,a method was proposed to estimate the rockingaffected depth using the fluctuation amplitude of the standpipe pressure difference.Application of this method in the drilling field has improved the rate of penetration and toolface stability,demonstrating the reliability and effectiveness of the methods proposed in this paper. 展开更多
关键词 Rocking drillstring slide drilling Drag reduction Drillstring mechanics Rocking parameter optimization
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Predicting impact forces on pipelines from deep-sea fluidized slides:A comprehensive review of key factors 被引量:1
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作者 Xingsen Guo Ning Fan +5 位作者 Defeng Zheng Cuiwei Fu Hao Wu Yanjun Zhang Xiaolong Song Tingkai Nian 《International Journal of Mining Science and Technology》 SCIE EI CAS CSCD 2024年第2期211-225,共15页
Deep-sea pipelines play a pivotal role in seabed mineral resource development,global energy and resource supply provision,network communication,and environmental protection.However,the placement of these pipelines on ... Deep-sea pipelines play a pivotal role in seabed mineral resource development,global energy and resource supply provision,network communication,and environmental protection.However,the placement of these pipelines on the seabed surface exposes them to potential risks arising from the complex deep-sea hydrodynamic and geological environment,particularly submarine slides.Historical incidents have highlighted the substantial damage to pipelines due to slides.Specifically,deep-sea fluidized slides(in a debris/mud flow or turbidity current physical state),characterized by high speed,pose a significant threat.Accurately assessing the impact forces exerted on pipelines by fluidized submarine slides is crucial for ensuring pipeline safety.This study aimed to provide a comprehensive overview of recent advancements in understanding pipeline impact forces caused by fluidized deep-sea slides,thereby identifying key factors and corresponding mechanisms that influence pipeline impact forces.These factors include the velocity,density,and shear behavior of deep-sea fluidized slides,as well as the geometry,stiffness,self-weight,and mechanical model of pipelines.Additionally,the interface contact conditions and spatial relations were examined within the context of deep-sea slides and their interactions with pipelines.Building upon a thorough review of these achievements,future directions were proposed for assessing and characterizing the key factors affecting slide impact loading on pipelines.A comprehensive understanding of these results is essential for the sustainable development of deep-sea pipeline projects associated with seabed resource development and the implementation of disaster prevention measures. 展开更多
关键词 Deep-sea fluidized slides Pipes Impact forces Shear behavior of slides Interface contact conditions Spatial relation
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基于Slide的研山铁矿高陡边坡稳定性分析 被引量:3
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作者 杨志彬 于世杰 +2 位作者 张太林 吕斌 羿立涛 《现代矿业》 CAS 2024年第2期136-139,共4页
露天矿山边坡稳定性对采场安全生产至关重要。为探究边坡施工过程中的安全隐患,以研山铁矿高陡边坡为研究对象,考虑爆破震动及地震作用荷载,运用Slide二维边坡数值模拟软件对典型剖面进行稳定性计算。结果表明:在正常工况条件、爆破震... 露天矿山边坡稳定性对采场安全生产至关重要。为探究边坡施工过程中的安全隐患,以研山铁矿高陡边坡为研究对象,考虑爆破震动及地震作用荷载,运用Slide二维边坡数值模拟软件对典型剖面进行稳定性计算。结果表明:在正常工况条件、爆破震动及地震作用下,边坡整体安全系数符合要求,整体处于稳定状态。但在爆破震动及地震作用下,边坡局部安全系数介于临界值,可能存在局部滑坡风险。为保证采场生产安全,提出了相应的边坡管理预防措施,为相关实践工作提供一定参考。 展开更多
关键词 BISHOP法 slide 安全系数 Morgenstern-Price法 高陡边坡
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Numerical analysis of downward progressive landslides in long natural slopes with sensitive clay 被引量:1
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作者 Yujia Zhang Xue Zhang +2 位作者 Xifan Li Aindra Lingden Jingjing Meng 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第10期3937-3950,共14页
Landslides occurring in sensitive clay often result in widespread destruction,posing a significant risk to human lives and property due to the substantial decrease in undrained shear strength during deformation.Assess... Landslides occurring in sensitive clay often result in widespread destruction,posing a significant risk to human lives and property due to the substantial decrease in undrained shear strength during deformation.Assessing the consequences of these landslides is challenging and necessitates robust numerical methods to comprehensively investigate their failure mechanisms.While studies have extensively explored upward progressive landslides in sensitive clays,understanding downward progressive cases remains limited.In this study,we utilised the nodal integration-based particle finite element method(NPFEM)with a nonlinear strain-softening model to analyse downward progressive landslides in sensitive clay on elongated slopes,induced by surcharge loads near the crest.We focused on elucidating the underlying failure mechanisms and evaluating the effects of different soil parameters and strainsoftening characteristics.The simulation results revealed the typical pattern for downward landslides,which typically start with a localised failure in proximity to the surcharge loads,followed by a combination of different types of failure mechanisms,including single flow slides,translational progressive landslides,progressive flow slides,and spread failures.Additionally,inclined shear bands occur within spread failures,often adopting distinctive ploughing patterns characterised by triangular shapes.The sensitive clay thickness at the base,the clay strength gradient,the sensitivity,and the softening rate significantly influence the failure mechanisms and the extent of diffused displacement.Remarkably,some of these effects mirror those observed in upward progressive landslides,underscoring the interconnectedness of these phenomena.This study contributes valuable insights into the complex dynamics of sensitive clay landslides,shedding light on the intricate interplay of factors governing their behaviour and progression. 展开更多
关键词 Sensitive clay landslides Long natural slopes Translational progressive failure Flow slides Spread Nodal integration-based particle finite element method(N-PFEM)
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基于Slide2的某铁矿尾矿库坝体稳定性分析 被引量:1
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作者 王晓强 《山西冶金》 CAS 2024年第2期120-122,共3页
尾矿库是冶金矿山的重要附属设施,一旦失事将造成严重的环境污染和重大损失,尾矿库安全的核心在于尾矿坝是否稳定。通过采用Slide2软件,根据岩土工程勘察资料,建立山西某铁矿尾矿库坝体典型剖面的二维数值模型,对坝体三种运行工况下的... 尾矿库是冶金矿山的重要附属设施,一旦失事将造成严重的环境污染和重大损失,尾矿库安全的核心在于尾矿坝是否稳定。通过采用Slide2软件,根据岩土工程勘察资料,建立山西某铁矿尾矿库坝体典型剖面的二维数值模型,对坝体三种运行工况下的渗流稳定性和坝坡稳定性进行分析,以确定尾矿库的安全性,并分析Slide2软件应用于尾矿坝稳定性分析中的可靠性和功能性。 展开更多
关键词 铁矿尾矿库 slide2软件 渗流稳定性 抗滑稳定性
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Insight into the Permeability and Microstructure Evolution Mechanism of the Sliding Zone Soil: A Case Study from the Huangtupo Landslide, Three Gorges Reservoir, China
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作者 Qianyun Wang Huiming Tang +6 位作者 Pengju An Kun Fang Junrong Zhang Minghao Miao Qingwen Tan Lei Huang Shengming Hu 《Journal of Earth Science》 SCIE CAS CSCD 2024年第3期941-954,共14页
A large number of laboratory investigations related to the permeability have been conducted on the sliding zones.Yet little attention has been paid to the particular sliding zones of the slideprone Badong Formation.He... A large number of laboratory investigations related to the permeability have been conducted on the sliding zones.Yet little attention has been paid to the particular sliding zones of the slideprone Badong Formation.Here,we experimentally investigate the permeability nature and the mechanism of seepage in the viscous sliding zone of the Huangtupo Landslide.Saturated seepage tests have been performed first with consideration of six dry densities and thirteen hydraulic gradients,in conjunction with the mercury intrusion porosimetry test and scanning electron microscopy test for the microstructure analysis after seepage.The results show that seepage in the sliding zone soil does not follow Darcy’s Law,since there is a threshold hydraulic gradient(i0)below which no flow is observed and a critical hydraulic gradient(icr)over which the hydraulic conductivity(K)tends to be stable.The percentage of bound water could be responsible for the occurrence of i0 and icr.Furthermore,pore size distributions(PSD)less than 0.6µm and between 10 and 90µm exhibit positive and negative correlations with the i0,respectively,indicating that the i0 is related to the PSD.The mechanism accounting for this result is that pore water pressure forces fine clay particles into the surrounding large pores and converts arranged particles to discretely distributed ones,thereby weakening the connectivity of pores.The seepages in the sliding zones behave differently from that in the sliding mass and sliding bed in response to the permeability. 展开更多
关键词 RESERVOIR LANDslideS sliding zone soil PERMEABILITY MICROSTRUCTURE seepage.
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Three-dimensional CSAMT Forward Modeling of Potential Landslide Sliding Surfaces Using Finite Element Method
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作者 Ruo Wang Qingyun Di +3 位作者 Da Lei Changmin Fu Pengfei Liang Miaoyue Wang 《Applied Geophysics》 SCIE CSCD 2024年第4期621-638,878,共19页
Landslides are a type of natural disaster that can cause substantial harm to humanity.Monitoring and predicting the initiation of potential landslides is critical to avoiding losses due to disasters and economic activ... Landslides are a type of natural disaster that can cause substantial harm to humanity.Monitoring and predicting the initiation of potential landslides is critical to avoiding losses due to disasters and economic activities.The impact of the controlled-source audio-frequency magnetotelluric method on investigating landslide surfaces is assessed through numerical simulations with a finite element approach.A Dirichlet boundary condition is selected to match the truncated boundary,resulting in a remarkable improvement in simulation efficiency.Rederivation of the formulas for a layered medium adept to the controlled-source audiofrequency magnetotelluric method is necessary to determine the electromagnetic field at any location along the truncated boundary.After the reliability evaluation of the new codes,a landslide model with a slide surface is designed,and the characteristics of its electromagnetic field and the apparent resistivity are studied.Instead of the total electromagnetic field,which is strongly infl uenced by topography variation,the apparent resistivity should be used for sliding surface detection.The normalized pure anomalous electromagnetic field may also be employed to quickly assess the detectability of the sliding surface.Overall,this study demonstrates that the controlled-source audio-frequency magnetotelluric method can be employed for investigating landslides,and recommends survey parameters,including configuration,frequency range,and length of survey line in landslide exploration. 展开更多
关键词 CSAMT slide surface modeling truncated boundary survey parameters
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CrossLinkNet: An Explainable and Trustworthy AI Framework for Whole-Slide Images Segmentation
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作者 Peng Xiao Qi Zhong +3 位作者 Jingxue Chen Dongyuan Wu Zhen Qin Erqiang Zhou 《Computers, Materials & Continua》 SCIE EI 2024年第6期4703-4724,共22页
In the intelligent medical diagnosis area,Artificial Intelligence(AI)’s trustworthiness,reliability,and interpretability are critical,especially in cancer diagnosis.Traditional neural networks,while excellent at proc... In the intelligent medical diagnosis area,Artificial Intelligence(AI)’s trustworthiness,reliability,and interpretability are critical,especially in cancer diagnosis.Traditional neural networks,while excellent at processing natural images,often lack interpretability and adaptability when processing high-resolution digital pathological images.This limitation is particularly evident in pathological diagnosis,which is the gold standard of cancer diagnosis and relies on a pathologist’s careful examination and analysis of digital pathological slides to identify the features and progression of the disease.Therefore,the integration of interpretable AI into smart medical diagnosis is not only an inevitable technological trend but also a key to improving diagnostic accuracy and reliability.In this paper,we introduce an innovative Multi-Scale Multi-Branch Feature Encoder(MSBE)and present the design of the CrossLinkNet Framework.The MSBE enhances the network’s capability for feature extraction by allowing the adjustment of hyperparameters to configure the number of branches and modules.The CrossLinkNet Framework,serving as a versatile image segmentation network architecture,employs cross-layer encoder-decoder connections for multi-level feature fusion,thereby enhancing feature integration and segmentation accuracy.Comprehensive quantitative and qualitative experiments on two datasets demonstrate that CrossLinkNet,equipped with the MSBE encoder,not only achieves accurate segmentation results but is also adaptable to various tumor segmentation tasks and scenarios by replacing different feature encoders.Crucially,CrossLinkNet emphasizes the interpretability of the AI model,a crucial aspect for medical professionals,providing an in-depth understanding of the model’s decisions and thereby enhancing trust and reliability in AI-assisted diagnostics. 展开更多
关键词 Explainable AI security TRUSTWORTHY CrossLinkNet whole slide images
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基于SLIDE软件的某矿山排土场稳定性分析
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作者 高仲谋 李娇娇 +3 位作者 胡家仓 毕建春 官伟 刘金鑫 《世界有色金属》 2024年第14期43-46,共4页
为研究某矿山排土场稳定性,使用SLIDE软件,采用简化Bishop法、Janbu修正法和Spencer法对该排土场自然工况、降雨工况和地震工况下的安全系数进行计算。结果表明,该排土场边坡在自然和降雨工况下处于稳定,在地震工况下处于基本稳定,由此... 为研究某矿山排土场稳定性,使用SLIDE软件,采用简化Bishop法、Janbu修正法和Spencer法对该排土场自然工况、降雨工况和地震工况下的安全系数进行计算。结果表明,该排土场边坡在自然和降雨工况下处于稳定,在地震工况下处于基本稳定,由此为该排土场将来的维护和治理作业提供了参考价值。 展开更多
关键词 排土场 稳定性 安全系数 slide软件 极限平衡法
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基于自适应滑模控制器的PMSM调速策略研究 被引量:1
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作者 王要强 王秋旭 +2 位作者 聂福全 张晓光 梁军 《郑州大学学报(理学版)》 CAS 北大核心 2025年第1期88-94,共7页
为了提高永磁同步电机的调速性能,滑模控制逐渐取代PI控制被引入控制系统中。但是传统滑模控制中趋近律的趋近速度慢与固有抖振问题制约着滑模控制的发展,为此提出一种改进的滑模趋近律。首先,为了解决传统等速趋近律中趋近速度和抖振... 为了提高永磁同步电机的调速性能,滑模控制逐渐取代PI控制被引入控制系统中。但是传统滑模控制中趋近律的趋近速度慢与固有抖振问题制约着滑模控制的发展,为此提出一种改进的滑模趋近律。首先,为了解决传统等速趋近律中趋近速度和抖振难以平衡的问题,在所提趋近律中引入系统状态变量,并在滑模增益中引入指数项,使其在保证趋近速度的同时抑制滑模抖振。其次,由于开关函数在零点附近具有不连续的特性,会引起滑模抖振,为此采用sat函数代替常规开关函数,能够在保证响应速度的前提下抑制滑模抖振。然后,基于所提趋近律,设计永磁同步电机的滑模速度控制器。最后,仿真和实验结果表明,所提趋近律可以提高永磁同步电机调速系统的控制性能。 展开更多
关键词 永磁同步电机 滑模控制 自适应趋近律 sat函数 系统状态量
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基于滑动窗口和斜率特征的振弦式传感器数据清洗方法 被引量:1
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作者 陈建勋 陈辉 +3 位作者 罗彦斌 罗华 陈浩 李昌鹏 《中国公路学报》 北大核心 2025年第5期134-145,共12页
隧道结构健康监测自诊断和状态评估都是建立在数据分析的基础上,但传感器所获取的数据不可避免地会出现诸多异常数据。这些异常数据不仅包含非结构性因素引起的干扰信息,还包括结构性因素引起的损伤信息。如何提取淹没在异常数据中的有... 隧道结构健康监测自诊断和状态评估都是建立在数据分析的基础上,但传感器所获取的数据不可避免地会出现诸多异常数据。这些异常数据不仅包含非结构性因素引起的干扰信息,还包括结构性因素引起的损伤信息。如何提取淹没在异常数据中的有用损伤信息,并剔除无用的干扰信息成为了重点。根据异常数据变化率的不稳定、不连续性,提出一种滑动斜率异常检测和数据重构法。首先,采用滑动窗口对数据进行动态分段处理,再对各窗口内数据进行最小二乘线性拟合,得到斜率和截距向量;其次,根据斜率的方差和拟合优度设置阈值,检测并剔除离散程度较大、拟合程度较差的斜率和截距值;最后,利用回归计算和中位数法进行数据重构。基于钢筋混凝土试件损伤试验数据和现场监测的异常数据,对所提方法与传统3σ法、滑动中值滤波、小波变换和经验模态分解法的应用效果进行对比。结果表明:所提方法能够有效清洗其他方法难以处理的增益和偏移数据,能有效识别和清洗数据的异常趋势,同时不破坏原有的结构性损伤数据,保证了监测数据的质量,能够满足实际应用的需要。 展开更多
关键词 隧道工程 时间序列数据 数据清洗 滑动斜率检测法 振弦式传感器 滑动窗口 损伤试验
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基于RBF网络的四旋翼无人机姿态鲁棒自适应反步滑模控制 被引量:3
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作者 刘金华 王远 +1 位作者 张智轩 李涛 《江苏大学学报(自然科学版)》 CAS 北大核心 2025年第1期36-42,共7页
针对存在干扰的四旋翼无人机姿态系统,设计了一种RBF网络鲁棒自适应反步滑模控制器.在反步滑模控制的基础上,通过RBF网络逼近和补偿标称控制律,采用神经网络最小参数学习法,取神经网络的权值上界估计作为神经网络的估计值,通过设计参数... 针对存在干扰的四旋翼无人机姿态系统,设计了一种RBF网络鲁棒自适应反步滑模控制器.在反步滑模控制的基础上,通过RBF网络逼近和补偿标称控制律,采用神经网络最小参数学习法,取神经网络的权值上界估计作为神经网络的估计值,通过设计参数估计自适应律来代替神经网络权值的调整,并用Lyapunov理论证明系统的稳定性.仿真结果表明:该方法相比反步滑模控制方法,在有干扰的情况下,有更短的调节时间,更好的跟踪精度,验证了本方法具有更好的抗干扰性和鲁棒性. 展开更多
关键词 四旋翼无人机 姿态控制 反步滑模控制 RBF神经网络 鲁棒自适应控制
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一种基于AEKF的铆接件视觉伺服精确装配方法 被引量:3
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作者 李宗刚 李彦博 +1 位作者 焦建军 杜亚江 《系统仿真学报》 北大核心 2025年第1期107-118,共12页
针对工业生产中存在多轴孔铆接件因铆钉数量多、铆钉与铆孔间隙小、铆钉分布不规则等特点,致使装配过程约束复杂,装配精度要求高,难以实现铆接工艺智能化以提升装配效率问题,提出一种基于自适应扩展卡尔曼滤波的铆接件视觉伺服精确装配... 针对工业生产中存在多轴孔铆接件因铆钉数量多、铆钉与铆孔间隙小、铆钉分布不规则等特点,致使装配过程约束复杂,装配精度要求高,难以实现铆接工艺智能化以提升装配效率问题,提出一种基于自适应扩展卡尔曼滤波的铆接件视觉伺服精确装配方法。为实现铆接件装配时的高精度定位,在传统扩展卡尔曼滤波的基础上,引入自适应噪声估计器,消除未知环境下的系统噪声对图像雅可比矩阵估计精度的影响,保证视觉伺服过程中图像雅可比矩阵的高精度估计;为保证铆接件装配时视觉伺服运动轨迹平滑稳定,设计滑模控制器,对铆接件进行轨迹跟踪,同时引入最小二乘法对铆接件图像特征深度信息进行实时在线估计,实现铆接件的高精度装配;以6自由度机器人建立仿真模型,结果表明在分布不规则的铆钉中选取4个铆钉的圆心点特征作为控制输入,通过设计的视觉伺服控制器能够完成铆接件的高精度多轴孔装配,提高了铆接工艺中关键工序的智能化水平。 展开更多
关键词 铆接 多轴孔装配 自适应扩展卡尔曼滤波 深度在线估计 滑模控制
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