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Mechanism and evolution of a deep-seated liquefaction-induced flow slide disaster chain triggered by the M 6.2 Jishishan earthquake,Gansu,China
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作者 Li Zhaoyan Wang Zifa Yuan Jinyuan 《Earthquake Engineering and Engineering Vibration》 2026年第1期1-12,共12页
On December 18,2023,a magnitude 6.2 earthquake struck Jishishan County,Gansu Province,triggering a liquefaction-induced flow slide along the loess-mudstone contact zone and causing significant casualties and property ... On December 18,2023,a magnitude 6.2 earthquake struck Jishishan County,Gansu Province,triggering a liquefaction-induced flow slide along the loess-mudstone contact zone and causing significant casualties and property losses.The event featured low-slope,large-scale,runout distance sliding and exhibited a clear cascading disaster chain.Its characteristics closely resemble the catastrophic mudflow at the nearby Lajia Ruins approximately 4,000 years ago.Using high-resolution oblique photogrammetry,cone penetration testing,surface wave analysis,and horizontal-to-vertical spectral ratio methods,this study examines the stratigraphy,groundwater conditions,and geomechanical properties of the affected zone.Results indicate that saturated loess overlying impermeable mudstone formed a high-moisture mass vulnerable to seismic disturbance.Seismic resonance triggered the liquefaction of weakly structured loess,which slide along the contact interface and evolved into a runout distance mudflow.Underground water and terrain modification created a composite weak zone of saturated loess and softened mudstone,which intensified the disaster chain-from earthquake to liquefaction,flow slide,and mudflow.This study contributes to the understanding of deep-seated liquefaction-flow slide disasters,thereby advancing more effective risk mitigation strategies in the Loess Plateau and comparable loess-covered seismic regions. 展开更多
关键词 Jishishan earthquake Lajia Ruins coupled disaster chain deep-seated liquefaction liquefaction-induced flow slide
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Application of Whole Slide Imaging Technology in Clinical Pathological Diagnosis
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作者 Zhenjie Wang Jianguo Huai 《Journal of Clinical and Nursing Research》 2026年第1期21-26,共6页
Whole Slide Imaging (WSI) technology, as a revolutionary digital technology in the field of pathology, is gradually changing the traditional clinical pathological diagnosis model. By converting traditional glass patho... Whole Slide Imaging (WSI) technology, as a revolutionary digital technology in the field of pathology, is gradually changing the traditional clinical pathological diagnosis model. By converting traditional glass pathological sections into complete digital images through high-resolution scanning, it provides a new method for pathological diagnosis. Based on this, this paper studies the application of WSI technology in clinical pathological diagnosis, elaborates on its application value, analyzes the current application status, and proposes corresponding application countermeasures, aiming to provide reference for the standardized and popularized development of this technology in clinical pathological diagnosis. 展开更多
关键词 Whole slide imaging(WSI)technology Clinical pathological diagnosis Application value Current status Application countermeasures
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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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基于新型趋近律的表贴式永磁同步电机抗扰滑模控制策略
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作者 王要强 陈晨 +3 位作者 张世达 聂福全 张晓光 梁军 《电力系统保护与控制》 北大核心 2026年第2期151-161,共11页
针对表贴式永磁同步电机(permanent magnet synchronous motor,PMSM)转速环存在的负载扰动、参数失配等不确定性问题,提出一种基于新型趋近律的抗扰滑模控制策略。首先,提出一种新型自适应趋近律,所提趋近律在等速项中引入系统滑模变量... 针对表贴式永磁同步电机(permanent magnet synchronous motor,PMSM)转速环存在的负载扰动、参数失配等不确定性问题,提出一种基于新型趋近律的抗扰滑模控制策略。首先,提出一种新型自适应趋近律,所提趋近律在等速项中引入系统滑模变量的自适应增益,解决了传统指数趋近律收敛速度与滑模抖振的矛盾问题,减小了跟踪误差,且避免了趋近速度突变问题。然后,基于所提新型趋近律和非奇异积分终端滑模面设计了转速环滑模控制器。最后,为进一步提高系统的抗扰性能,设计扩展滑模扰动观测器观测并补偿转速环的不确定性扰动。仿真与实验结果表明,所提抗扰滑模控制策略能有效提高电机调速系统的动态性能和鲁棒性。 展开更多
关键词 永磁同步电机 滑模控制 新型趋近律 动态性能 鲁棒性
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不确定地磁分数阶混沌系统滑模同步的两个方案
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作者 毛北行 王东晓 王建军 《安徽大学学报(自然科学版)》 北大核心 2026年第1期10-15,共6页
地磁混沌系统在导航、定位、气象等领域有着广泛的应用前景.基于两个滑模同步控制方案研究不确定地磁分数阶混沌系统的同步,根据滑模控制与分数阶微积分,巧妙设计控制输入量实现其自适应滑模同步调节,并对两个控制方案所取得的结果进行... 地磁混沌系统在导航、定位、气象等领域有着广泛的应用前景.基于两个滑模同步控制方案研究不确定地磁分数阶混沌系统的同步,根据滑模控制与分数阶微积分,巧妙设计控制输入量实现其自适应滑模同步调节,并对两个控制方案所取得的结果进行了对比与分析. 展开更多
关键词 分数阶 地磁混沌 不确定 滑模
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基于非线性增益超螺旋滑模观测器的无刷直流电机控制
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作者 胡鸿志 苏弘杰 +3 位作者 颜宝贤 苏海涛 管芳 徐翠锋 《组合机床与自动化加工技术》 北大核心 2026年第2期85-90,95,共7页
针对传统超螺旋滑模观测器(ST-SMO)在无传感器无刷直流电机控制过程中存在高频抖振以及转子位置观测滞后的问题,提出一种基于非线性增益的超螺旋滑模观测器(NGST-SMO)。在超螺旋算法中引入非线性增益及线性项,提高算法的收敛速度;采用so... 针对传统超螺旋滑模观测器(ST-SMO)在无传感器无刷直流电机控制过程中存在高频抖振以及转子位置观测滞后的问题,提出一种基于非线性增益的超螺旋滑模观测器(NGST-SMO)。在超螺旋算法中引入非线性增益及线性项,提高算法的收敛速度;采用softsign函数代替传统的符号函数,消除SMO观测反电动势中的高频分量;针对无传感器控制系统中速度环控制抗扰动能力差的问题,将NGST-SMO与扰动观测器结合,提升闭环控制系统的抗扰动能力,增强系统的鲁棒性。基于仿真模型和BLDC试验平台的实验表明,在所提出的NGST-SMO控制下,相比ST-SMO观测转速的抖振降低了78%,转子位置观测误差降低85%,并且提高了系统的动态响应性能。 展开更多
关键词 滑模观测器 无传感器控制 扰动观测器 无刷直流电机
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融合滑动窗口与改进SGBM的高分辨率目标检测与测距研究
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作者 丁建军 汪刚林 +4 位作者 陈正超 张超 夏礼恒 夏骏麒 孙超 《光学技术》 北大核心 2026年第1期86-93,共8页
随着成像技术的发展,高分辨率图像广泛应用于多个领域,但在复杂天气、多尺度变化和立体匹配复杂度高等条件下仍面临挑战。提出一种结合滑动窗口的目标检测与测距方法,在处理高分辨率图像时,采用滑动窗口法对图像进行分割并保留20%的重... 随着成像技术的发展,高分辨率图像广泛应用于多个领域,但在复杂天气、多尺度变化和立体匹配复杂度高等条件下仍面临挑战。提出一种结合滑动窗口的目标检测与测距方法,在处理高分辨率图像时,采用滑动窗口法对图像进行分割并保留20%的重叠区域,随后将各子图输入至YOLOv8模型进行检测。为提升模型性能,在backbone中引入GCANet模块以增强雾霾环境下的图像质量,并加入HorBlock以提升多尺度特征表征能力。检测完成后,合并各子图结果,并采用引入了CIoU匹配机制的非极大值抑制算法(NMS)进行后处理,以缓解密集目标场景中的过抑制问题。最后,设计了基于检测框约束的局部匹配算法,结合加权最小二乘滤波(WLS)补全视差空洞。实验结果表明,在自制的雾天场景Fog-A数据集与公开的无人机视角VisDrone2019数据集上,方法相较于原始YOLOv8n模型,mAP分别提升9.8%和6.1%;匹配时间缩短至原SGBM的三分之一,精度提升0.7%。 展开更多
关键词 成像光学 高分辨率 滑动窗口 目标检测 YOLOV8n SGBM
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基于潜在滑动面倾角离散的铁路路基重力式挡土墙主动土压力计算方法
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作者 李斌 袁锦全 +3 位作者 张联宇 曹子君 姚洪锡 陈嵘 《岩土工程学报》 北大核心 2026年第1期88-95,共8页
铁路路基重力式挡土墙墙后填土断面为梯形,且填土承受列车荷载。这种复杂工程条件下,危险滑动面位置和主动土压力无法通过库仑土压力公式确定,导致挡土墙稳定性分析十分困难。首先基于滑动土体的极限平衡,提出一种危险滑动面的搜索方法... 铁路路基重力式挡土墙墙后填土断面为梯形,且填土承受列车荷载。这种复杂工程条件下,危险滑动面位置和主动土压力无法通过库仑土压力公式确定,导致挡土墙稳定性分析十分困难。首先基于滑动土体的极限平衡,提出一种危险滑动面的搜索方法,计算主动土压力合力;根据合力等效与总力矩等效原则,确定主动土压力水平和竖直分量的力臂,在此基础上,计算分析铁路路基重力式挡土墙考虑滑动和倾覆两种失效模式下的稳定性。结果表明该方法计算准确、简单且计算量小,限制条件少,能很好地适用于复杂工程条件;当倾角变化步长为0.01°时可同时兼顾计算精度与计算效率。此外,针对超载分布位置、超载宽度、墙背倾角及内边坡坡角等因素开展参数影响分析,总结了主动土压力大小、主动土压力作用位置及各失效模式安全性受各参数的影响规律。 展开更多
关键词 重力式挡土墙 危险滑动面 主动土压力 挡土墙稳定性
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强风化碳质板岩滑带的水岩作用特征和劣化机制研究
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作者 杨校辉 朱文杰 +1 位作者 郭楠 朱彦鹏 《工程地质学报》 北大核心 2026年第1期79-92,共14页
碳质板岩广泛分布于白龙江流域的堆积层滑坡中,强风化碳质板岩遇水软化为泥状滑带土,但其水岩作用特征与强度劣化驱动滑坡复活的机制尚不明确。以江顶崖滑坡滑带土为例,本文通过崩解试验、干湿循环试验(模拟季节性降雨)和原位剪切试验(1... 碳质板岩广泛分布于白龙江流域的堆积层滑坡中,强风化碳质板岩遇水软化为泥状滑带土,但其水岩作用特征与强度劣化驱动滑坡复活的机制尚不明确。以江顶崖滑坡滑带土为例,本文通过崩解试验、干湿循环试验(模拟季节性降雨)和原位剪切试验(100~600 kPa),阐明了强风化碳质板岩的强度劣化特性,结合物理模型试验与数值模拟,揭示了滑带土“疲劳损伤-应变演化-滑带劣化-滑坡复活”的联动劣化机制。结果表明:(1)伴生亲水黏土矿物吸水膨胀导致滑带土332 min内崩解,干湿循环作用下黏土矿物的循环胀缩诱发结构疲劳损伤,导致宏观裂缝扩展与强度损失,单轴抗压强度经20次干湿循环下降12.6%;(2)浅层滑带(<37.5 m)在低正应力(<300 kPa)下呈应变软化,而深层滑带因高应力(>300 kPa)表现为应变硬化;(3)降雨模型试验表明,浅层滑带含水率上升加速裂缝扩展与蠕滑变形,形成“劣化-入渗”恶性循环,降雨4 h后裂缝贯通,48 h内滑坡前缘位移达14.58 mm;(4)滑坡复活由浅层应变软化和深层卸荷再软化循环驱动,滑坡动态复活受控于浅层蠕滑卸荷与深层应力调整的耦合效应。研究成果可为白龙江流域堆积层滑坡防治和重大工程建设提供科学依据。 展开更多
关键词 堆积层滑坡 碳质板岩 水岩作用 劣化机制 滑带
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互补滑模PD控制在桥式起重机中的应用
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作者 邵雪卷 吕恩智 +1 位作者 陈志梅 赵志诚 《控制工程》 北大核心 2026年第2期371-378,共8页
针对欠驱动桥式起重机系统的定位防摆问题,提出了互补滑模PD控制策略。在小车位移、负载摆角及各自一阶微分的状态误差作为变量所组成的线性滑模面的基础上,引入位移与摆角的误差积分形成积分滑模面,并对应设计一个补充滑模面来形成互... 针对欠驱动桥式起重机系统的定位防摆问题,提出了互补滑模PD控制策略。在小车位移、负载摆角及各自一阶微分的状态误差作为变量所组成的线性滑模面的基础上,引入位移与摆角的误差积分形成积分滑模面,并对应设计一个补充滑模面来形成互补滑模控制,使系统变量运行空间限制在滑模面的相交处,缩短变量到滑模面的距离,进而提升系统的快速性。同时,引入对负载摆角的PD补偿控制,增强对负载摆角的抑制能力,使小车的运行更加平稳,并构造Lyapunov函数证明了系统的稳定性。仿真和实验结果验证了该控制策略对定位和防摆的有效性。 展开更多
关键词 桥式吊车 互补滑模控制 PD补偿控制 定位防摆 LYAPUNOV函数
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微凸起金属滑动密封性能的理论及试验研究
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作者 李富平 梁晓阳 +3 位作者 郭连超 王信鹏 柏林清 谷磊 《润滑与密封》 北大核心 2026年第1期160-167,共8页
为解决石油钻完井领域中井下工具橡塑密封件在高温、高压及复杂介质环境下耐久性不足的问题,提出一种基于金属微凸起结构的滑动密封技术。该密封由带有金属凸起的活塞和金属套筒组成密封副,活塞凸起与金属套筒间过盈配合,利用微凸体挤... 为解决石油钻完井领域中井下工具橡塑密封件在高温、高压及复杂介质环境下耐久性不足的问题,提出一种基于金属微凸起结构的滑动密封技术。该密封由带有金属凸起的活塞和金属套筒组成密封副,活塞凸起与金属套筒间过盈配合,利用微凸体挤压变形达到密封效果。对金属微凸起滑动密封技术进行理论分析与试验研究,分析过盈量、微凸起形状以及配副材料对最大接触应力、最大Mises应力及预紧力的影响。结果表明:过盈量是影响密封性能的主要因素,随着过盈量的增加,最大接触应力、最大Mises应力和预紧力明显增加,当过盈量为0.1~0.15 mm时密封性能最佳;与过盈量相比,凸起形状和活塞套筒材料对密封性能的影响较小。为降低密封副安装过程中的磨损失效,以较小的预紧力与最大接触应力比值为优选准则,通过正交试验优选出最佳的密封配副尺寸和配副材料并进行密封性能试验。优选后的金属密封配副在120℃下的最大密封压力不低于105 MPa,满足密封要求。该研究为高苛刻工况下钻完井工具密封提供了一种新型金属密封解决方案。 展开更多
关键词 金属密封 滑动密封 接触应力 预紧力 密封性能
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基于IPSO-NTSMC的光伏MPPT控制方法
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作者 常雨芳 罗梦瑶 +2 位作者 高鹏 严怀成 黄文聪 《太阳能学报》 北大核心 2026年第1期82-88,共7页
针对局部阴影下光伏阵列输出功率的多峰值问题,提出一种将改进粒子群算法和非奇异终端滑模控制融合的复合控制方法。首先,分析光伏阵列的数学模型及输出特性;其次,设计改进粒子群算法,减小惯性权重在算法执行过程中的影响,提高局部阴影... 针对局部阴影下光伏阵列输出功率的多峰值问题,提出一种将改进粒子群算法和非奇异终端滑模控制融合的复合控制方法。首先,分析光伏阵列的数学模型及输出特性;其次,设计改进粒子群算法,减小惯性权重在算法执行过程中的影响,提高局部阴影下光伏系统的输出功率;再次,设计非奇异终端滑模切换面,以克服传统滑模的奇异问题,简化系统结构并提高稳态精度;最后,通过Matlab/Simulink平台开展仿真实验,并与现有方法进行对比,结果表明所提策略在跟踪速度、稳态功率波动等方面均表现出更优性能,可显著改善光伏系统的最大功率点跟踪效果。 展开更多
关键词 光伏阵列 太阳电池 滑模控制 最大功率点跟踪 粒子群优化算法
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基于PSO-SMO的分布式驱动车辆轮胎力级联估计
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作者 王姝 杨再杰 +1 位作者 赵轩 吕洋 《重庆理工大学学报(自然科学)》 北大核心 2026年第1期27-35,共9页
针对传统以轮胎模型为基础的轮胎力估计依赖准确的轮胎模型和路面附着系数等参数的缺点,提出一种基于粒子群优化滑模算法(PSO-SMO)的轮胎力级联估计器。首先,考虑车辆运动时的质心偏移和悬架运动,建立车辆载荷转移模型估计轮胎垂向力;同... 针对传统以轮胎模型为基础的轮胎力估计依赖准确的轮胎模型和路面附着系数等参数的缺点,提出一种基于粒子群优化滑模算法(PSO-SMO)的轮胎力级联估计器。首先,考虑车辆运动时的质心偏移和悬架运动,建立车辆载荷转移模型估计轮胎垂向力;同时,以车轮动力学模型为基础,基于PSO-SMO估计算法设计轮胎纵向力估计器。在此基础上,以纵向力和垂向力估计值为已知信息,结合前轮转角、横摆角速度等参数,基于PSO-SMO估计算法实现侧向力估计。最后在Carsim-Simulink联合仿真平台下进行仿真试验。结果表明,在不同行驶工况下,该估计器能够有效估计轮胎力,相比传统观测器收敛速度更快,估计精度更高,尤其是在附着系数变化的路面下鲁棒性更强。 展开更多
关键词 质心偏移 粒子群优化算法 滑模观测器 轮胎力
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