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Slip Model Used for Prediction of r Value of BCC Metal Sheets from ODF Coefficients
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作者 PAN Hao WANG Xiao-ming 《Journal of Iron and Steel Research International》 SCIE EI CAS CSCD 2000年第1期36-38,共3页
Different slip models were used for prediction of r value of BCC metal sheets from ODF coefficients.According to the maximum plastic work theory developed by Bishop and Hill,it is expected that the higher of Taylor fa... Different slip models were used for prediction of r value of BCC metal sheets from ODF coefficients.According to the maximum plastic work theory developed by Bishop and Hill,it is expected that the higher of Taylor factors given by a slip’ model,the better prediction obtained based on the model.From this point of view,a composed slip model of BCC metals was presented.Based on the model,the agreement of predicted r values for deep drawing steels with experimental ones is excellent. 展开更多
关键词 bcc metals r values slip model texture
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Hybrid Slip Model for Near-Field Ground Motion Estimation Based on Uncertainty of Source Parameters
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作者 孙晓丹 陶夏新 +1 位作者 汤爱平 路建波 《Transactions of Tianjin University》 EI CAS 2010年第1期61-67,共7页
The hybrid slip model used to generate a finite fault model for near-field ground motion estimation and seismic hazard assessment was improved to express the uncertainty of the source form of a future earthquake.In th... The hybrid slip model used to generate a finite fault model for near-field ground motion estimation and seismic hazard assessment was improved to express the uncertainty of the source form of a future earthquake.In this process, source parameters were treated as normal random variables, and the Fortran code of hybrid slip model was modified by adding a random number generator so that the code could generate many finite fault models with different dimensions and slip distributions for a given magnitude.Furth... 展开更多
关键词 hybrid slip model uncertainty of source parameters optimal finite fault model near-field ground motion estimation
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一种HESLIP的彩色图像去雾新算法
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作者 冯玉颖 吴敬怡 王文鼎 《计算机与网络》 2026年第1期76-81,共6页
随着雾霾的日益严重,图像去雾的研究变得越来越重要。针对雾霾天气导致的图像降质、现有去雾算法难以兼顾去雾效果与细节保留问题,整合物理层面的暗通道先验去雾模型(HE模型)与对称对数图像处理(Symmetric Logarithmic Image Processing... 随着雾霾的日益严重,图像去雾的研究变得越来越重要。针对雾霾天气导致的图像降质、现有去雾算法难以兼顾去雾效果与细节保留问题,整合物理层面的暗通道先验去雾模型(HE模型)与对称对数图像处理(Symmetric Logarithmic Image Processing, SLIP)模型的技术优势,构建了一种适用于彩色图像的对称对数物理去雾(HE-SLIP Fusion-Based Color Image Dehazing, HESLIP)算法。HESLIP算法执行流程是根据物理模型对彩色图像去雾;运用SLIP模型对彩色图像的I分量开展变换操作;利用彩色图像S分量的非线性指数调整模型以实现雾天图像的清晰化。与已有的去雾算法相比,HESLIP算法达到了更好的去雾效果。为验证算法性能,对HESLIP算法与已有的去雾算法进行了对比仿真与主客观评价测试。测试结果表明,所提算法在标准差、对比度和平均梯度方面都明显优于现有算法。HESLIP算法不仅能实现高效的图像去雾,还能有效保留图像边缘等细节信息的完整性,为彩色雾天图像的清晰化处理提供了更优方案。 展开更多
关键词 物理模型 对称对数图像处理 去雾 对称对数物理去雾
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Slip model for the 2011 M_w 9.0 Sendai (Japan) earthquake and its M_w 7.9 aftershock derived from GPS data 被引量:8
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作者 DIAO FaQi XIONG Xiong +2 位作者 NI SiDao ZHENG Yong GE Can 《Chinese Science Bulletin》 SCIE EI CAS 2011年第27期2941-2947,共7页
用为 8 h 的测量 GPS 的 coseismic 和 seismic 以后排水量跟随 M w 2011 年 3 月 11 日, coseismic 和 seismic 以后差错的 9.0 仙台地震滑动模型基于一个分层的外壳的模型被开发。主要吃惊的测地学的时刻大小是被测量近似 M w 8.98。... 用为 8 h 的测量 GPS 的 coseismic 和 seismic 以后排水量跟随 M w 2011 年 3 月 11 日, coseismic 和 seismic 以后差错的 9.0 仙台地震滑动模型基于一个分层的外壳的模型被开发。主要吃惊的测地学的时刻大小是被测量近似 M w 8.98。slip 展出清楚的反向的特征,与大约 23.3 m 的 hypocenter,和大小附近的最大值。某罢工滑倒行为可以发生在山峰破裂地区的二个方面上。主要吃惊释放的几乎 90% 地震时刻发生在深度不到 40 km。精力由差错释放了在跟随主要吃惊的 8 h 滑倒近似等于 M w 的地震 8.13。与 1.5 m 的最大值, seismic 以后滑倒在 coseismic 破裂差错的西南的部分被集中,它与 M w 的地点和行为同意很好 7.9 余震。这暗示在在主要吃惊以后的 8 h 的 seismic 以后变丑被 M w 主要导致 7.9 余震。另外, seismic 以后 0.20.4 m 滑倒在 coseismic 破裂的下面剧降延期被观察,它可能被在滑倒以后的效果在这个时期期间引起了。 展开更多
关键词 GPS数据 余震 滑模式 断层滑动 GPS测量 破裂带 地震矩 地壳模型
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Static slip model of the M_w 9.0 Tohoku (Japan) earthquake:Results from joint inversion of terrestrial GPS data and seafloor GPS/acoustic data 被引量:9
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作者 DIAO FaQi XIONG Xiong ZHENG Yong 《Chinese Science Bulletin》 SCIE CAS 2012年第16期1990-1997,共8页
Based on co-seismic displacements recorded by terrestrial GPS stations and seafloor GPS/acoustic stations, the static slip model of the 2011 Mw 9.0 Tohoku earthquake was determined by inverting the data using a layere... Based on co-seismic displacements recorded by terrestrial GPS stations and seafloor GPS/acoustic stations, the static slip model of the 2011 Mw 9.0 Tohoku earthquake was determined by inverting the data using a layered earth model. According to a priori information, the rupture surface was modeled with a geometry that is close to the actual rupture, in which the fault dip angle increases with depth and the fault strike varies with the trend of the trench. As shown by the results inferred from the joint inversion, the "geodetic" moment is 3.68 × 10 22 Nm, corresponding to Mw 9.01, and the maximum slip is positioned at a depth of 13.5 km with a slip magnitude of 45.8 m. Rupture asperities with slip exceeding 10 m are mainly distributed from 39.6 to 36.97°N, over a length of almost 240 km along the trench. The slip was mostly concentrated at depths shallower than 40 km, up-dip of the hypocenter. "Checkerboard" tests reveal that a joint inversion of multiple datasets can resolve the slip distribution better than an inversion with terrestrial GPS data only-especially when aiming to resolve slip at shallow depths. Thus, the joint inversion results obtained by this work may provide a more reliable slip model than the results of other studies that are only derived from terrestrial GPS data or seismic waveform data. 展开更多
关键词 GPS数据 联合反演 滑移模型 地震位移 地面 海底 静态 东北
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Continuum-based slip model and its validity for micro-channel flows 被引量:3
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作者 ZHANG Genxuan LIU Minghou +3 位作者 ZHANG Xianfeng YE Taohong CHEN Yiliang WANG Lu 《Chinese Science Bulletin》 SCIE EI CAS 2006年第9期1130-1137,共8页
In this paper, the low Mach number he- lium and nitrogen flows in micro-channels are inves- tigated numerically with variations of inlet to outlet pressure ratios, aspect ratios, out pressures and fluid mediums by usi... In this paper, the low Mach number he- lium and nitrogen flows in micro-channels are inves- tigated numerically with variations of inlet to outlet pressure ratios, aspect ratios, out pressures and fluid mediums by using different continuum-based slip models. Theoretical solutions based on perturbation expansions of the Navier-Stokes equations have been developed under different order slip conditions. The validity of slip models has been examined by the corresponding experiments and the DSMC method at different Knudsen numbers. Simulations have shown good predictions of the compressibility, rarefaction and thermal creep effects on micro-channel flows with the present slip models. The higher order slip models relatively decrease the rarefaction effects comparing with a first-order slip model. Both of the Knudsen number and the Reynolds number have been identified as key parameters, which govern the rarefaction effects and thermal creep effects, respec- tively. The present slip models have been also dem- onstrated to be appropriate for micro-channel nitro- gen flows with the Knudsen number less than 0.15, and the higher order slip conditions improve the Na- vier-Stokes predictions in the slip flow regime with Kn<0.08. However, the continuum-based slip models significantly under-predict the rarefaction effects in the transitional flow regime as the Knudsen number exceeds 0.2. 展开更多
关键词 微通道 滑移模型 扰动分析 稀疏效应 克努森数
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Finite element method for coupled diffusion-deformation theory in polymeric gel based on slip-link model 被引量:1
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作者 Hengdi SU Huixian YAN Bo JIN 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2018年第4期581-596,共16页
A polymeric gel is an aggregate of polymers and solvent molecules, which can retain its shape after a large deformation. The deformation behavior of polymeric gels was often described based on the Flory-Rehner free en... A polymeric gel is an aggregate of polymers and solvent molecules, which can retain its shape after a large deformation. The deformation behavior of polymeric gels was often described based on the Flory-Rehner free energy function without considering the influence of chain entanglements on the mechanical behavior of gels. In this paper,a new hybrid free energy function for gels is formulated by combining the EdwardsVilgis slip-link model and the Flory-Huggins mixing model to quantify the time-dependent concurrent process of large deformation and mass transport. The finite element method is developed to analyze examples of swelling-induced deformation. Simulation results are compared with available experimental data and show good agreement. The influence of entanglements on the time-dependent deformation behavior of gels is also demonstrated.The study of large deformation kinetics of polymeric gel is useful for diverse applications. 展开更多
关键词 polymeric gel finite element method slip-link model large deformation mass transport kinetics
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A Clot Model Examination: with Impulsion of Nanoparticles under Influence of Variable Viscosity and Slip Effects 被引量:1
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作者 S.Ijaz Iqra Shahzadi +1 位作者 S.Nadeem Anber Saleem 《Communications in Theoretical Physics》 SCIE CAS CSCD 2017年第11期667-677,共11页
In this speculative analysis, our main focused is to address the neurotic condition that occurs due to accumulation of blood components on the wall of the artery that results in blood coagulation. Specifically, to per... In this speculative analysis, our main focused is to address the neurotic condition that occurs due to accumulation of blood components on the wall of the artery that results in blood coagulation. Specifically, to perceive this phenomena clot model is considered. To discuss this analysis mathematical model is formed in the presence of the effective thermal conductivity and variable viscosity of base fluid. Appropriate slip conditions are employed to obtain the close form solutions of temperature and velocity profile. The graphical illustrations have been presented for the assessment of pressure rise, pressure gradient and velocity profile. The effects of several parameters on the flow quantities for theoretical observation are investigated. At the end, the results confirmed that the impulsion of copper and silver nanoparticles as drug agent enlarges the amplitude of the velocity and hence nanoparticles play an important role in engineering and biomedical applications such as drug delivery system. 展开更多
关键词 variable viscosity metallic nanoparticles slip effects clot model exact solution
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Studying mechanism of anisotropic crack generation on C-,R-,A-,and M-planes of sapphire during ultra-precision orthogonal cutting using a visualized slip/fracture activation model
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作者 Suk Bum Kwon Sangkee Min 《Nanotechnology and Precision Engineering》 CSCD 2024年第4期47-64,共18页
With the growing demand for the fabrication of microminiaturized components,a comprehensive understanding of material removal behavior during ultra-precision cutting has become increasingly significant.Single-crystal ... With the growing demand for the fabrication of microminiaturized components,a comprehensive understanding of material removal behavior during ultra-precision cutting has become increasingly significant.Single-crystal sapphire stands out as a promising material for microelectronic components,ultra-precision lenses,and semiconductor structures owing to its exceptional characteristics,such as high hardness,chemical stability,and optical properties.This paper focuses on understanding the mechanism responsible for generating anisotropic crack morphologies along various cutting orientations on four crystal planes(C-,R-,A-,and M-planes)of sapphire during ultra-precision orthogonal cutting.By employing a scanning electric microscope to examine the machined surfaces,the crack morphologies can be categorized into three distinct types on the basis of their distinctive features:layered,sculptured,and lateral.To understand the mechanism determining crack morphology,visualized parameters related to the plastic deformation and cleavage fracture parameters are utilized.These parameters provide insight into both the likelihood and direction of plastic deformation and fracture system activations.Analysis of the results shows that the formation of crack morphology is predominantly influenced by the directionality of crystallographic fracture system activation and by the interplay between fracture and plastic deformation system activations. 展开更多
关键词 Anisotropic behavior Crack morphology slip/fracture activation model Single-crystal sapphire Ultra-precision machining
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注塑成型充填流动单向局部多尺度模拟及熔接线缺陷研究
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作者 任梦柯 刘耘溥 +3 位作者 李征 谷俊峰 阮诗伦 申长雨 《计算力学学报》 北大核心 2026年第1期46-52,67,共8页
注塑成型制品的缺陷与高分子微观结构密切相关。本文将改进后的光滑粒子动力学(SPH)方法与聚合固定滑移链模型(CFSM)结合,建立了一种新的注塑充填过程单向局部多尺度模拟方法。通过对两种圆环型腔的注塑充填过程进行多尺度模拟,提取了... 注塑成型制品的缺陷与高分子微观结构密切相关。本文将改进后的光滑粒子动力学(SPH)方法与聚合固定滑移链模型(CFSM)结合,建立了一种新的注塑充填过程单向局部多尺度模拟方法。通过对两种圆环型腔的注塑充填过程进行多尺度模拟,提取了平均缠结点数、链段取向度等微观结构参数进行对比,研究了熔接线和熔合线的微观结构特性。模拟结果表明,引入尾部突出可以减小熔接线区域长度,将部分熔接线区域转变为熔合线,改善制品的力学性能。 展开更多
关键词 多尺度模拟 注塑成型 光滑粒子动力学 滑移链模型 熔接线
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Testing and modeling of cyclically loaded rock anchors 被引量:5
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作者 Joar Tistel Gustav Grimstad Gudmund Eiksund 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2017年第6期1010-1030,共21页
The Norwegian Public Roads Administration(NPRA) is planning for an upgrade of the E39 highway route at the westcoast of Norway. Fixed links shall replace ferries at seven fjord crossings. Wide spans and large depths a... The Norwegian Public Roads Administration(NPRA) is planning for an upgrade of the E39 highway route at the westcoast of Norway. Fixed links shall replace ferries at seven fjord crossings. Wide spans and large depths at the crossings combined with challenging subsea topography and environmental loads call for an extension of existing practice. A variety of bridge concepts are evaluated in the feasibility study. The structures will experience significant loads from deadweight, traffic and environment. Anchoring of these forces is thus one of the challenges met in the project. Large-size subsea rock anchors are considered a viable alternative. These can be used for anchoring of floating structures but also with the purpose of increasing capacity of fixed structures. This paper presents first a thorough study of factors affecting rock anchor bond capacity. Laboratory testing of rock anchors subjected to cyclic loading is thereafter presented. Finally, the paper presents a model predicting the capacity of a rock anchor segment, in terms of a ribbed bar, subjected to a cyclic load history. The research assumes a failure mode occurring in the interface between the rock anchor and the surrounding grout. The constitutive behavior of the bonding interface is investigated for anchors subjected to cyclic one-way tensile loads. The model utilizes the static bond capacity curve as a basis, defining the ultimate bond sbuand the slip s1 at τ. A limited number of input parameters are required to apply the model. The model defines the bond-slip behavior with the belonging rock anchor capacity depending on the cyclic load level(τcy/τ), the cyclic load ratio(R= τcy/τcy), and the number of load cycles(N). The constitutive model is intended to model short anchor lengths representing an incremental length of a complete rock anchor. 展开更多
关键词 Rock anchor Rock bolt Bond-slip model Cyclic loading Empirical model Laboratory testing Bond degradation
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基于履带滑动的爬壁机器人移动分析
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作者 梁佧楠 宋屹峰 +3 位作者 常勇 王洪光 林松 张頔 《科学技术与工程》 北大核心 2026年第4期1558-1564,共7页
为了解决履带式爬壁机器人壁面移动准确性低的问题,通过建立机器人在壁面上的动力学模型,提出一种基于履带滑转率优化的机器人速度补偿方法。首先,为了深入分析爬壁机器人的运动机理,基于旋量理论建立了适用于不同壁面倾角环境的爬壁机... 为了解决履带式爬壁机器人壁面移动准确性低的问题,通过建立机器人在壁面上的动力学模型,提出一种基于履带滑转率优化的机器人速度补偿方法。首先,为了深入分析爬壁机器人的运动机理,基于旋量理论建立了适用于不同壁面倾角环境的爬壁机器人动力学模型;然后,引入履带剪切理论,根据机器人移动过程中左右履带的滑转率,推导出实际移动时电机所需的纠正转速,实现速度补偿与轨迹纠偏;之后,通过MATLAB仿真,得到了机器人在不同位姿下的最小安全吸附力以及吸附过程中滑移率随吸附力的变化趋势;最后,根据现有试验样机进行了实验验证。结果表明:引入滑转率的动力学模型能够更贴合机器人实际移动时的位姿变化,引入速度补偿后机器人姿态纠正超过61%。可见基于滑转率的速度补偿方法对于移动精度和运行效率都有显著提升,并为改进爬壁机器人的尺寸设计和前馈补偿运动控制提供参考。 展开更多
关键词 爬壁机器人 负压吸附 动力学模型 滑转率 速度补偿
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走滑型断溶体形成机制与油气成藏研究进展
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作者 王露露 代宗仰 +3 位作者 李阳 高洋 任铌 郭子家 《地质科技通报》 北大核心 2026年第1期95-109,共15页
断溶体在国内多数盆地普遍发育,其资源量巨大,已经成为地学界研究的热点课题。但由于其埋藏深、勘探难度大,对断溶体的圈闭划分、形成机制、发育控制因素观点不一,亟需形成一致的认识。首先回顾了断溶体的基本概念,指出其具有埋藏深、... 断溶体在国内多数盆地普遍发育,其资源量巨大,已经成为地学界研究的热点课题。但由于其埋藏深、勘探难度大,对断溶体的圈闭划分、形成机制、发育控制因素观点不一,亟需形成一致的认识。首先回顾了断溶体的基本概念,指出其具有埋藏深、非均质性强、流体性质差异大等特点,并强调了走滑断层在油气储集和运移中的重要作用。通过对塔里木盆地顺北地区及其他地区的地质数据进行分析,揭示了断溶体的圈闭类型、形成机制及其控藏因素。研究认为走滑断层的分段性、溶蚀流体的活动以及烃类的及时侵位对断溶体油气藏的发育至关重要。此外,研究了大气淡水、热液流体和烃类流体在储层改造中的作用,及如何共同影响断溶体油气藏的形成和分布。总结了断溶体油气藏的成藏模式。本研究有助于开拓新的油气勘探领域和方向。 展开更多
关键词 断溶体 圈闭类型 形成机制 控藏作用 走滑断层 成藏模式
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带基础隔震器结构的Stick-slip运动模型 被引量:2
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作者 冯奇 张相庭 《同济大学学报(自然科学版)》 EI CAS CSCD 北大核心 2000年第4期430-433,共4页
带基础隔振器结构的Stick-slip运动研究是一个很年轻的课题.有关文献指出:带可滑动基础的结构存在Stick-slip运动的可能,它将导致结构失稳以及由此引起疲劳破坏,因此该类结构的Stick-slip运动研究是... 带基础隔振器结构的Stick-slip运动研究是一个很年轻的课题.有关文献指出:带可滑动基础的结构存在Stick-slip运动的可能,它将导致结构失稳以及由此引起疲劳破坏,因此该类结构的Stick-slip运动研究是有价值的.据此,调查了在地震作用下带滑动基础或基础隔振器结构,并建立其Stick-slip运动的离散动力学模型,指出了系统的复杂的非线性特性. 展开更多
关键词 基础隔振器 离散动力学 抗震设计
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Analytical Solution for Peristaltic Transport of Viscous Nanofluid in an Asymmetric Channel with Full Slip and Convective Conditions
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作者 Abdelhalim Ebaid Emad H. Aly K. Vajravelu 《Communications in Theoretical Physics》 SCIE CAS CSCD 2017年第7期96-102,共7页
The peristaltic ttow of nanofluids is a relatively new area of research. Scientists are of the opinion that the no-slip conditions at the boundaries are no longer valid and consequently, the first and the second order... The peristaltic ttow of nanofluids is a relatively new area of research. Scientists are of the opinion that the no-slip conditions at the boundaries are no longer valid and consequently, the first and the second order slip conditions should be addressed. In this paper, the effects of slip conditions and the convective boundary conditions at the boundary walls on the peristaltic flow of a viscous nanofluid are investigated for. Also, the exact analytical solutions are obtained for the model. The obtained results are presented through graphs and discussed. The results reveal that the two slip parameters have strong effects on the temperature and the nanoparticles volume fraction profiles. Moreover, it has been seen that the temperature and nanoparticles volume fraction profiles attain certain values when the first slip condition exceeds a specified value. However, no limit value for the second slip parameter has been detected. Further, the effects of the various emerging parameters on the flow and heat transfer characteristics have been presented. 展开更多
关键词 NANOFLUID peristaltic flow slip model convective conditions asymmetric channel
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滑坡作用下抗滑桩及桥梁桩基变形机制模型试验研究
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作者 宁峙名 吴红刚 +3 位作者 刘旭 李凯 徐汶瀚 庞军 《铁道标准设计》 北大核心 2026年第1期101-109,142,共10页
为研究滑坡作用下桥梁桩基的承载机理及受力模式,分析有无抗滑桩加固时各结构物的变形机制,以兰新高铁二十里铺特大桥25号桥墩滑坡典型断面为背景,开展大型室内模型试验,对比分析有无抗滑桩支护时桥梁桩基的桩顶位移、桩周土压力及弯矩... 为研究滑坡作用下桥梁桩基的承载机理及受力模式,分析有无抗滑桩加固时各结构物的变形机制,以兰新高铁二十里铺特大桥25号桥墩滑坡典型断面为背景,开展大型室内模型试验,对比分析有无抗滑桩支护时桥梁桩基的桩顶位移、桩周土压力及弯矩分布规律。研究结果表明:(1)有抗滑桩支护时桥梁桩基桩顶位移大大减小,抗滑桩对桥梁桩基有明显的加固作用;(2)无桩组桥梁桩基山侧土压力沿桩深呈“R”形分布,河侧土压力沿桩深呈“D”形分布,桥基承受荷载能力有限,土压力分布形式发生改变,桩体中上部桩周土压力较大,在设计时应重点考虑优化;(3)有桩组桥梁桩基山侧及河侧土压力桩深均呈“S”形分布,抗滑桩承担绝大部分的滑坡推力,经抗滑桩传递至桥梁桩基的剩余滑坡推力大大降低,桥梁桩基有足够的能力抵抗滑坡作用,使其山侧和河侧的土体变形表现出协调一致性,桥梁桩基得到很好的保护;(4)各级滑坡推力作用下,有、无桩组桩身弯矩分布特征基本一致,沿深度方向均呈“S”形分布,弯矩最大值均位于滑带处。相同荷载有桩侧弯矩差值较无桩侧得到很大改善,桥基受力分布更加均匀,抗滑桩桩身最大弯矩值是有桩侧桥梁桩基最大弯矩值的13.5倍,抗滑桩支护效果显著。 展开更多
关键词 铁路桥梁 边坡工程 群桩基础 抗滑桩 变形机制 模型试验
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油气开发工程诱发地震研究现状及未来展望
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作者 孙子涵 李玉伟 +4 位作者 唐慧敏 彭根博 陈天宇 崔光磊 陈胜男 《石油科学通报》 2026年第1期114-130,共17页
中国油气资源分布广泛,开发潜力大,发展速度快,但页岩气、致密油等非常规油气资源的勘探开发仍处于初期阶段。随着国内油气能源需求量的持续增长,深部非常规油气资源的开采已成为国家能源工程领域重点关注的问题。然而,非常规油气开采... 中国油气资源分布广泛,开发潜力大,发展速度快,但页岩气、致密油等非常规油气资源的勘探开发仍处于初期阶段。随着国内油气能源需求量的持续增长,深部非常规油气资源的开采已成为国家能源工程领域重点关注的问题。然而,非常规油气开采工程普遍涉及向深部地层大规模注入流体。流体注入会扰动原岩应力场,改变地下断层的应力状态,可能导致断层失稳滑移并诱发地震灾害。因此,评估与预防此类人为工程扰动诱发地震风险,已成为实现资源安全可持续开发的关键课题。近年来,全球多个深部能源工程在开采阶段均监测到地震事件,经震后分析表明,这些地震与注入流体扰动断层失稳之间存在显著的时空关联。例如,韩国浦项和瑞士巴塞尔的地热项目,就因诱发显著地震而被迫中止。事实上,我国油气田地质条件更为复杂,断层滑移失稳条件、滑移模式和滑移量难以准确预判,断层发育区附近开采施工参数难以确定。为了在非常规油气资源开发中实现收益与风险的平衡,当前深部能源开采所引发的环境地质问题及其伴生地震灾害的预测与防治是亟待攻克的问题。本文通过梳理国内外能源开发工程中典型的诱发地震案例,重点分析了开发现场断层滑移失稳的应力条件与诱发机理,总结了断层滑移失稳模式,诱发地震判据、地震影响范围和震级预测模型,讨论了开发过程中人为工程扰动和环境地质因素对诱发地震事件的影响。最后,本研究总结了当前研究中亟待解决的主要问题与技术挑战,并从数值模拟、实验方法及现场监测3个方向对未来研究进行了展望。本研究可以推动油气开发作业诱发地震的基础认知,对减少或避免潜在地震灾害的发生具有实际意义和工程价值。 展开更多
关键词 油气开发工程 水力压裂 断层滑移 诱发地震 地震预测模型
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基于Slip-Link模型的凝胶大变形与扩散耦合瞬态问题分析 被引量:2
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作者 苏恒迪 颜慧贤 金波 《力学季刊》 CSCD 北大核心 2017年第4期681-692,共12页
长链聚合物通过化学键,范德华力等相互作用交联构成的弹性体吸收溶剂后形成聚合物凝胶.聚合物凝胶的溶胀变形过程是溶剂在凝胶网络内的扩散、迁移与凝胶网络变形耦合作用的结果.通常,研究凝胶的扩散-变形耦合问题是基于经典的Flory-Reh... 长链聚合物通过化学键,范德华力等相互作用交联构成的弹性体吸收溶剂后形成聚合物凝胶.聚合物凝胶的溶胀变形过程是溶剂在凝胶网络内的扩散、迁移与凝胶网络变形耦合作用的结果.通常,研究凝胶的扩散-变形耦合问题是基于经典的Flory-Rehner自由能模型进行的,然而该自由能函数由于忽略了凝胶网络链段相互缠绕引起的物理交联对凝胶弹性网络自由能的影响,在计算大变形与扩散耦合问题时误差较大.本文基于Edwards-Vilgis slip-link弹性模型和Flory-Huggins混合理论构建能反映聚合物网络链缠结拓扑限制作用的凝胶自由能函数,并结合凝胶的运动方程和扩散方程,得到能够反映链段缠结影响的凝胶大变形与扩散耦合瞬态方程,并基于此研究网络缠结对凝胶在受压状态下变形梯度和凝胶内溶剂的名义浓度的影响. 展开更多
关键词 聚合物凝胶 slip-link模型 大变形 扩散 瞬态
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足式机器人SLIP模型向上跳跃台阶的运动控制 被引量:1
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作者 肖乐 伞红军 +1 位作者 孙海杰 陈久朋 《控制理论与应用》 EI CAS CSCD 北大核心 2024年第4期631-637,共7页
由于存在地势起伏,台阶对足式机器人运动稳定性会带来较大挑战.弹簧负载倒立摆模型(SLIP)作为研究足式机器人的优良模板,能否完成向上跳跃台阶的动作与其腿部摆角,起跳位置和跳跃高度都有密切的关系.由于调整模型腿部摆角规律容易引发... 由于存在地势起伏,台阶对足式机器人运动稳定性会带来较大挑战.弹簧负载倒立摆模型(SLIP)作为研究足式机器人的优良模板,能否完成向上跳跃台阶的动作与其腿部摆角,起跳位置和跳跃高度都有密切的关系.由于调整模型腿部摆角规律容易引发运动失效,故本文在算法中引入虚拟弹簧腿,根据虚拟弹簧腿的运行规律确定合理起跳位置,根据起跳位置来控制系统跳跃高度进而完成跳跃台阶的动作.最后利用仿真软件进行多组仿真,结果表明本文算法对起跳区间划分合理,对起跳高度控制精准,能够实现SLIP模型跳跃台阶前后的稳定运动. 展开更多
关键词 足式机器人 运动控制 slip模型 台阶地形 能量补充
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基于FMPC的智能草坪修剪机器人轨迹跟踪控制
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作者 耿洋洋 郭志军 +2 位作者 王丁健 李洪涛 庞明天 《农机化研究》 北大核心 2026年第6期164-170,共7页
为了使智能草坪修剪机器人能够适用于不同的草坪工况,确保跟踪控制的准确性,提出了一种基于模糊模型预测控制(FMPC)轨迹跟踪算法。首先,针对驱动轮在作业过程中固有的滑移与滑转特性,建立了相应的运动学模型和横向误差模型;其次,通过模... 为了使智能草坪修剪机器人能够适用于不同的草坪工况,确保跟踪控制的准确性,提出了一种基于模糊模型预测控制(FMPC)轨迹跟踪算法。首先,针对驱动轮在作业过程中固有的滑移与滑转特性,建立了相应的运动学模型和横向误差模型;其次,通过模糊控制器处理环境中草坪密度和高度等变量,利用预设的模糊规则优化机器人的横向速度,并结合参考轨迹作为模型预测控制(MPC)的期望目标,从而设计出适用于轨迹跟踪控制的FMPC控制器,实现对机器人的实时状态调整;最后,通过MatLab/Simulink仿真进行验证,结果显示:在不同路面附着系数下,该算法均表现出良好的控制效果。在路面附着系数为0.5的情况下,机器人的最大横向误差和航向角误差的跟踪精度分别提升了28.76%和17.02%;在附着系数为0.2时,上述指标的跟踪精度则分别提升了31.18%和19.51%。实车试验结果表明:机器人的横向误差均值低于0.25 m,所提出的算法在草坪路面上具备良好的轨迹跟踪性能。 展开更多
关键词 智能草坪修剪机器人 轨迹跟踪控制 模糊模型预测控制 滑移率 滑转率
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