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Upper-Bound Limit Analysis of the Multi-Layer Slope Stability and Failure Mode Based on Generalized Horizontal Slice Method

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Journal of Earth Science 2024年第3期35卷 929-940页

作者： Huawei Zhang Changdong Li Wenqiang Chen Ni Xie Guihua Wang Wenmin Yao Xihui Jiang jingjing long Key Laboratory of Geotechnical Mechanics and Engineering of Ministry of Water Resources Changjiang River Scientific Research InstituteWuhan 430010China Faculty of Engineering China University of GeosciencesWuhan 430074China Badong National Observation and Research Station of Geohazards China University of GeosciencesWuhan 430074China School of Civil Engineering Zhengzhou UniversityZhengzhou 450001China

Multi-layer slopes are widely found in clay residue receiving fields.A generalized horizontal slice method(GHSM)for assessing the stability of multi-layer slopes that considers the energy dissipation between adjacent horizontal slices is *** view of the upper-bound limit analysis theory,the energy equation is derived and the ultimate failure mode is generated by comparing the sliding surface passing through the slope toe(mode A)with that below(mode B).In addition,the influence of the number of slices on the stability coefficients in the GHSM is studied and the stable value is *** to the original method(Chen’s method),the GHSM can acquire more precise results,which takes into account the energy dissipation in the inner sliding soil ***,the GHSM,limit equilibrium method(LEM)and numerical simulation method(NSM)are applied to analyze the stability of a multi-layer slope with different slope angles and the results of the safety factor and failure mode are very close in each *** ultimate failure modes are shown to be mode B when the slope angle is not more than 28°.It illustrates that the determination of the ultimate sliding surface requires comparison of multiple failure modes,not only mode A.

关键词： stability and failure mode slope stability generalized horizontal slice method upperbound limit analysis energy dissipation geotechnical engineering.

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面部起病的感觉运动神经元病1例报道

云南医药 2024年第3期45卷 113-114页

作者：龙晶晶张昆林孟强林岚梅茸云南省第一人民医院/昆明理工大学附属医院神经内科云南昆明650100

1临床资料患者女性、 57岁,“因口周麻木9月”于2021年9月入院。患者9月前无诱因出现口周麻木、抬头困难、咀嚼费力、吞咽困难,伴头晕、头痛、四肢乏力、饮水呛咳。逐渐加重出现梳头、抬手困难、言语不清。病程中无发热、肌肉酸痛、肌... 详细信息

1临床资料患者女性、 57岁,“因口周麻木9月”于2021年9月入院。患者9月前无诱因出现口周麻木、抬头困难、咀嚼费力、吞咽困难,伴头晕、头痛、四肢乏力、饮水呛咳。逐渐加重出现梳头、抬手困难、言语不清。病程中无发热、肌肉酸痛、肌肉跳动,起病以来,进食费力、量少,体重下降7kg,余无特殊。查体:轻度构音障碍,角膜反射右眼消失、左眼减弱。额纹对称、闭目有力,鼻唇沟对称,伸舌居中,可见舌肌纤颤,鼓腮无力,双侧咽反射消失。双侧胸锁乳突肌、冈上肌、冈下肌、斜方肌、三角肌、肱二头肌、肱三头肌萎缩;抬头肌力Ⅱ级,转头肌力Ⅲ级,双上肢近端肌力肌力Ⅲ级,远端肌力Ⅴ(—)级,双下肢肌力Ⅴ级;四肢肌张力正常、腱反射活跃(+++),双侧Hoffmann征(+),双侧掌颌反射(—),右下肢Babinsk’s (+)。辅助检查:血生化、甲状腺功能、体液免疫、抗核抗体谱、肿瘤标志物,未见异常。MRI示:颈椎间盘变性,颈4/5,颈5/6椎间盘轻度膨出;颈4/5,颈5/6节段黄韧带轻度增厚。肺部CT示:双肺散在粟粒样结节,多考虑感染性病灶,肺结核待排。

关键词：神经系统疾病运动神经元病面部

Clues from networks:quantifying relational risk for credit risk evaluation of SMEs

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Financial Innovation 2022年第1期8卷 2467-2507页

作者： jingjing long Cuiqing Jiang Stanko Dimitrov Zhao Wang School of Management Hefei University of TechnologyHefei 230009AnhuiPeople’s Republic of China The Philosophy and Social Sciences Laboratory of Data Science and Intelligent Society Governance Ministry of EducationHefeiAnhuiPeople’s Republic of China Department of Management Sciences University of Waterloo200 University Avenue WestWaterlooON N2L 3G1Canada

Owing to information asymmetry,evaluating the credit risk of small-and mediumsized enterprises(SMEs)is *** previous studies evaluating the credit risk of SMEs have mostly focused on intrinsic risk generated by SMEs,our study considers both intrinsic and relational risks generated by neighbor firms’publicly available risk *** propose a framework for quantifying relational risk based on publicly available risk events for SMEs’credit risk *** proposed framework quantifies relational risk by weighting the impact of publicly available risk events of each firm in an interfirm network—considering the impact of interfirm network type,risk event type,and time dependence of risk events—and combines the relational risk score with financial and demographic features to evaluate SMEs credit *** results reveal that relational risk score significantly improves both discrimination and granting performances of credit risk evaluation of SMEs,providing valuable managerial and practical implications for financial institutions.

关键词： SMEs Credit risk evaluation Interfirm network Risk event Relational risk

少数民族老年人认知功能障碍与居住地改变相关性的研究进展

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神经损伤与功能重建 2024年第5期19卷 296-298页

作者：张蕾徐梅龙晶晶米凯娜颜蓉赵忠云南省第一人民医院昆明理工大学附属医院神经内科昆明650032 红河哈尼族彝族自治州第三人民医院肿瘤内二科云南省第一人民医院内科规培基地云南个旧661000

我国少数民族与汉族人群的认知功能障碍患病率存在差异。老年人居住地改变可能造成其认知功能的改变,其原因有社会人文环境改变、地理环境改变、心理应激等方面。本文对相关研究进展进行综述,以便预防和减缓少数民族人群认知功能障碍的... 详细信息

我国少数民族与汉族人群的认知功能障碍患病率存在差异。老年人居住地改变可能造成其认知功能的改变,其原因有社会人文环境改变、地理环境改变、心理应激等方面。本文对相关研究进展进行综述,以便预防和减缓少数民族人群认知功能障碍的发生发展。

关键词：少数民族认知障碍居住地改变

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On the Preparation of Low-Temperature-Rise and Low-Shrinkage Concrete Based on Phosphorus Slag

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Fluid Dynamics & Materials Processing 2024年第4期20卷 803-814页

作者： Jianlong Jin jingjing Ding long Xiong Ming Bao Peng Zeng China Construction Ready Mixed Concrete Co. Ltd.Wuhan430000China

The effects of different contents of a MgO expansive agent and phosphorus slag on the mechanical properties,shrinkage behavior,and the heat of hydration of concrete were *** slump flow,setting time,dry shrinkage,and hydration heat were used as sensitive parameters to assess the response of the considered *** shown by the results,in general,with an increase in the phosphorus slag content,the hydration heat of concrete decreases for all ages,but the early strength displays a downward trend and the dry shrinkage rate *** 90-d strength and dry shrinkage of concrete could be improved with a phosphorus residue content between 0%-20%,with the best performances in terms of mechanical properties and shrinkage characteristics being achieved for a content of 20 kg/m^(3).On the basis of these results,it can be concluded that appropriate amounts of phosphorus slag and MgO expansive agent can be used to improve the compressive strength of concrete in the later stage by reducing the hydration heat and dry shrinkage rate,respectively.

关键词： Phosphorus slag MgO expansion agent mass concrete hydration heat

Shearing Characteristics of Jurassic Silty Mudstone Slip Zone under Different Water Contents and Normal Stresses Based on Ring Shear Tests

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Journal of Earth Science 2022年

作者： Nang Mon Mon Thaw Changdong Li Zongxing Zou Wenqiang Chen jingjing long Aung Min Oo Dafalla Wadi Faculty of Engineering China University of Geosciences Badong National Observation and Research Station of Geohazards China University of Geosciences Department of Geology Hpa-An University 4. Department of Hydrogeology and Engineering Geology College of Petroleum Geology and Minerals University of Bahri

Landslides frequently occurred in Jurassic red strata in the Three Gorges Reservoir(TGR) region in China. The Jurassic strata consist of low mechanical strength and poor permeability of weak silty mudstone layer, which may cause slope instability during rainfall. In order to understand the strength behavior of Jurassic silty mudstone shear zone, the so-called Shizibao landslide located in Guojiaba Town, Zigui County, Three Gorges Reservoir(TGR) in China is selected as a case study. The shear strength of the silty mudstone shear zone is strongly influenced by the water content and normal stress. Therefore, a series of drained ring shear tests were carried out by changing the water contents(7%, 12%, 17%, and 20%, respectively) and normal stresses(200, 300, 400, and 500 k Pa, respectively).The result revealed that the residual friction coefficient and residual friction angle were power function relationships with water content and normal stress. The peak cohesion of the silty mudstone slip zone increased with water content to a certain limit, above which the cohesion decreased. In contrast, the residual cohesion showed the opposite trend, indicating the cohesion recovery above a certain limit of water content. However, both the peak and residual friction angle of the silty mudstone slip zone were observed to decrease steadily with increased water content. Furthermore, the macroscopic morphological features of the shear surface showed that the sliding failure was developed under high normal stress at low water content, while discontinuous sliding surface and soil extrusion were occurred when the water content increased to a saturated degree. The localized liquefaction developed by excess pore water pressure reduced the frictional force within the shear zone. Finally, the combined effects of the slope excavation and precipitation ultimately lead to the failure of the silty mudstone slope; however, continuous rainfall is the main factor triggering sliding.

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Calculation and Analysis of TVMS Considering Profile Shifts and Surface Wear Evolution Process of Spur Gear

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Chinese Journal of Mechanical Engineering 2024年第3期37卷 136-150页

作者： Wenzheng Liu Rupeng Zhu Wenguang Zhou jingjing Wang College of Mechanical and Electrical Engineering Nanjing University of Aeronautics and AstronauticsNanjingChina

Profile shift is a highly effective technique for optimizing the performance of spur gear transmission ***,tooth surface wear is inevitable during gear meshing due to inadequate lubrication and long-term *** profile shift and tooth surface wear(TSW)can impact the meshing characteristics by altering the involute tooth *** this study,a tooth stiffness model of spur gears that incorporates profile shift,TSW,tooth deformation,tooth contact deformation,fillet-foundation deformation,and gear body structure coupling is *** model efficiently and accurately determines the time-varying mesh stiffness(TVMS).Additionally,an improved wear depth prediction method for spur gears is developed,which takes into consideration the mutually prime teeth numbers and more accurately reflects actual gear meshing *** show that consideration of the mutual prime of teeth numbers will have a certain impact on the TSW ***,the finite element method(FEM)is employed to accurately verify the values of TVMS and load sharing ratio(LSR)of profile-shifted gears and worn *** study quantitatively analyzes the effect of profile shift on the surface wear process,which suggests that gear profile shift can partially alleviate the negative effects of *** contribution of this study provides valuable insights into the design and maintenance of spur gear systems.

关键词： Profile shift Tooth surface wear Structure coupling effect Improved wear depth prediction method TVMS

A stable implicit nodal integration-based particle finite element method(N-PFEM)for modelling saturated soil dynamics

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第6期16卷 2172-2183页

作者： Liang Wang Xue Zhang jingjing Meng Qinghua Lei Department of Earth Sciences ETH ZürichZürich8092Switzerland Department of Civil Engineering and Industrial Design University of LiverpoolLiverpoolL693BXUK Department of Civil Environmental and Natural Resources EngineeringLuleåUniversity of TechnologyLuleå97187Sweden Department of Earth Sciences Uppsala UniversityUppsala75105Sweden

In this study,we present a novel nodal integration-based particle finite element method(N-PFEM)designed for the dynamic analysis of saturated *** approach incorporates the nodal integration technique into a generalised Hellinger-Reissner(HR)variational principle,creating an implicit PFEM *** mitigate the volumetric locking issue in low-order elements,we employ a node-based strain smoothing *** discretising field variables at the centre of smoothing cells,we achieve nodal integration over cells,eliminating the need for sophisticated mapping operations after re-meshing in the *** express the discretised governing equations as a min-max optimisation problem,which is further reformulated as a standard second-order cone programming(SOCP)***,pore water pressure,and displacements are simultaneously determined using the advanced primal-dual interior point ***,our numerical model offers improved accuracy for stresses and pore water pressure compared to the displacement-based PFEM *** experiments demonstrate that the N-PFEM efficiently captures both transient and long-term hydro-mechanical behaviour of saturated soils with high accuracy,obviating the need for stabilisation or regularisation techniques commonly employed in other nodal integration-based PFEM *** work holds significant implications for the development of robust and accurate numerical tools for studying saturated soil dynamics.

关键词： Particle finite element method Nodal integration Dynamic saturated media Second-order cone programming(SOCP)

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我国翻译教材建设反思:现状、问题与对策

外语电化教学 2023年第1期 93-99页

作者：龙晶晶宫齐东莞理工学院文学与传媒学院广东省东莞市523808 暨南大学外国语学院广东省广州市510632

本文系统梳理了国内现有翻译教材的现状,以此为基础指出翻译教材建设的突出问题。针对现存问题,必须重点考虑现实需求,创新教材内容形式,推动翻译教材科学管理,建立完善审查监管机制,发挥思政价值,并通过开发翻译术语数据库,促进在线资... 详细信息

本文系统梳理了国内现有翻译教材的现状,以此为基础指出翻译教材建设的突出问题。针对现存问题,必须重点考虑现实需求,创新教材内容形式,推动翻译教材科学管理,建立完善审查监管机制,发挥思政价值,并通过开发翻译术语数据库,促进在线资源有效共享,从而在根本上推动我国翻译教材建设发展。

关键词：翻译教材建设问题对策语言服务