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Soil-atmosphere interaction in earth structures

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Journal of Rock Mechanics and Geotechnical Engineering 2022年第1期14卷 35-49页

作者： Yujun cui Laboratoire Navier Ecole des Ponts ParisTechFrance

The soil-atmosphere interaction was investigated through laboratory testing,field monitoring and numerical *** the laboratory,the soil water evaporation mechanisms were studied using an environmental chamber equipped with a large number of sensors for controlling both the air parameters and soil *** sand and clay were *** case of sand,a dry layer could be formed during evaporation in the near surface zone where the suction corresponded to the residual volumetric water *** evaporative surface was situated at a depth where the soil temperature was the *** case of clay,soil cracking occurred,changing the evaporative surface from one-dimensional to three-dimensional *** suctionbased evaporation model was adapted to take these phenomena into account by adopting a function of dry layer evolution in the case of sand and by adopting a surface crack ratio and a retative humidity ratio in the case of *** the field,the volumetric water content,and the suction as well as the runoff were monitored for an embankment constructed with lime/cement treated *** appeared that using precipitation data only did not allow a correct description of the variations of volumetric water content and suction inside the soils,the consideration of water evaporation being *** was possible to use a correlation between precipiration and *** hydraulic conductivity was found to be a key parameter controlling the variations of volumetric water content and *** the numerical modelling,a fully coupled thermohydraulic model was developed,allowing analyzing the changes in temperature,volumetric water content and suction of soil,with the upper boundary conditions at the interface between soil and atmosphere determined using meteorological *** between simulations and measurements showed the performance of such numerical approach.

关键词： Environmental chamber Soil water evaporation Suction-based evaporation model Embankment Field monitoring Numerical modeling

基于并联残差膨胀卷积网络的短文本实体关系联合抽取

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现代电子技术 2025年第2期48卷 169-178页

作者：曾伟奚雪峰崔志明苏州科技大学电子与信息工程学院江苏苏州215000 苏州市虚拟现实智能交互及应用技术重点实验室江苏苏州215000 苏州科技大学智慧城市研究院江苏苏州215000

关系抽取旨在从文本中提取出实体对之间存在的语义关系,但现有的关系抽取方法均存在关系冗余和重叠的不足,尤其是对于短文本,会因上下文信息不足而出现语义信息不足和噪声大等问题。此外,一般流水线式的关系抽取模型还存在误差传递问题... 详细信息

关系抽取旨在从文本中提取出实体对之间存在的语义关系,但现有的关系抽取方法均存在关系冗余和重叠的不足,尤其是对于短文本,会因上下文信息不足而出现语义信息不足和噪声大等问题。此外,一般流水线式的关系抽取模型还存在误差传递问题。为此,文中提出一种基于并联残差膨胀卷积网络的短文本实体关系联合抽取方法。该方法利用BERT生成语义特征信息,采用并联残差膨胀卷积网络来捕获语义信息,从而提升上下文信息的捕获能力并缓解噪声。联合抽取框架通过抽取潜在关系来过滤无关关系,然后再抽取实体以预测三元组,从而解决关系冗余和重叠问题,并提高计算效率。实验结果表明,与现有的主流模型相比,所提模型在三个公共数据集NYT、WebNLG和DuIE上的F1值分别为90.9%、91.3%和73.5%,相较于基线模型均有提升,验证了该模型的有效性。

关键词：实体关系抽取短文本残差膨胀卷积网络语义特征联合抽取 BERT编码器

Deposition pattern of stony and muddy debris flow at the confluence area

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Journal of Mountain Science 2021年第3期18卷 622-634页

作者： DU cui School of civil engineering Henan University of Science and TechnologyLuoyang 471023China

Debris flow fan affects the river profile and landscape *** propagation of multiple debris flows along a river can cause inundation and breaching risk,which can be exemplified by the Min River after the Wenchuan earthquake,Sichuan province,*** this work,large flume tests were conducted to examine the interactions between debris flows and water current with the fan geometry,momentum,runout distance,deposited width,the relative water level upstream and dominated *** results reveal that stony flow commonly travels at a high speed and forms a long rectangle shape fan,while the muddy flow generally travels at a low speed and forms a fan-shaped depositional *** stony flow can block a river even when the momentum is close to the water current;the muddy flow can block a river when the momentum is lower than that of water *** case of complete river damming,the relative water level upstream indicates that the inundation risk from the muddy flow damming river would be higher than the inundation risk of stony *** diversion ratio of muddy flow decreases as damming *** of dimensionless numbers reveals that stony flow is dominated by grain collision stress combined with turbulent mixing stress,while the muddy flow is dominated by viscous shear stress over friction *** fan geometry,damming ratio,diversion ratio,and the dominated stress all together indicate that stony flow strongly interacts with water current while the muddy flow does *** results can be helpful for understanding the physical interactions between water current and various debris flows,and debris flow dynamics at the channel confluence area.

关键词： Stony flows Muddy flows Physical interactions Damming ratio Dominated stress

Entire functions arising from trees

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Science China Mathematics 2021年第10期64卷 2231-2248页

作者： Weiwei cui Center for Mathematical Sciences Lund UniversityLund 22100Sweden

Given any infinite tree in the plane satisfying certain topological conditions,we construct an entire function f with only two critical values±1 and no asymptotic values such that f-1([-1,1])is ambiently homeomorphic to the given *** can be viewed as a generalization of the result of Grothendieck(see Schneps(1994))to the case of infinite ***,a similar idea leads to a new proof of the result of Nevanlinna(1932)and Elfving(1934).

关键词： entire function tree Shabat Riemann surface the type problem

Simplified procedure for controlling pressure distribution of a scramjet combustor

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Chinese Journal of Aeronautics 2014年第5期27卷 1137-1141页

作者： cui Tao School of Energy Science and Engineering Harbin Institute of Technology

Scramjet engines are used at extreme temperatures and velocity. New control problems involving distributed parameter control have been found concerning investigations of the control of scramjet engines whose physical states are spatially interacted. Succeeding the existing theoretical studies on the distributed parameter control for scramjet engines, this paper puts forward a simplified distributed parameter control approach for scramjet engines aimed at engineering application. The simplified control procedure uses the classical proportional-integral（PI） compensation to control the target pressure distribution of scramjet engines, which is effective and applicable for practical implements. Simulation results show the validation of the simplified distributed parameter control procedure.

关键词： Aeroengine Control Modeling Scramjet engine Supersonic combustion

Numerical Algorithm with Fourth-Order Spatial Accuracy for Solving the Time-Fractional Dual-Phase-Lagging Nanoscale Heat Conduction Equation

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Numerical Mathematics(Theory,Methods and Applications) 2023年第2期16卷 511-540页

作者： cui-cui Ji Weizhong Dai School of Mathematics and Statistics Qingdao UniversityQingdao 266071China Mathematics and Statistics Louisiana Tech UniversityRustonLA 71272USA

Nanoscale heat transfer cannot be described by the classical Fourier law due to the very small dimension,and therefore,analyzing heat transfer in nanoscale is of crucial importance for the design and operation of nano-devices and the optimization of thermal processing of ***,time-fractional dualphase-lagging(DPL)equations with temperature jump boundary conditions have showed promising for analyzing the heat conduction in *** article proposes a numerical algorithm with high spatial accuracy for solving the timefractional dual-phase-lagging nano-heat conduction equation with temperature jump boundary *** this end,we first develop a fourth-order accurate and unconditionally stable compact finite difference scheme for solving this time-fractional DPL *** then present a fast numerical solver based on the divide-and-conquer strategy for the obtained finite difference scheme in order to reduce the huge computational work and ***,the algorithm is tested by two examples to verify the accuracy of the scheme and computational *** we apply the numerical algorithm for predicting the temperature rise in a nano-scale silicon thin *** results confirm that the present difference scheme provides min{2−α,2−β}order accuracy in time and fourth-order accuracy in space,which coincides with the theoretical *** indicate that the mentioned time-fractional DPL model could be a tool for investigating the thermal analysis in a simple nanoscale semiconductor silicon device by choosing the suitable fractional order of Caputo derivative and the parameters in the model.

关键词： Nanoscale heat transfer fractional dual-phase-lagging model finite difference scheme stability convergence

Synthesis, Structures and Properties of C(sp^2)‐Centered Homo‐ and Hetero‐Nuclear Gold Complexes

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Chinese Journal of Chemistry 2019年第3期37卷 276-291页

作者： cui-cui Li Liang Zhao Key Laboratory of Bioorganic Phosphorus Chemistry&Chemical Biology Department of ChemistryTsinghua UniversityBeijing 100084China School of Chemistry and Chemical Engineering Beijing Institute of Technology Peking University

C(sp^2)‐centered homo‐ and hetero‐nuclear gold complexes have attracted widespread interests in recent decades. Studies of this type of complexes may deepen the understandings of the intermediates in Au‐catalyzed organic reactions and explore new applications in catalytic and material science. The focuses of this review include the synthesis, structural characteristics, properties and applications of C(sp^2)‐centered homo‐ and hetero‐nuclear gold complexes according to different structural classifications.

关键词： Homo homo

Analysis of a Free Boundary Problem Modeling Tumor Growth

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Acta Mathematica Sinica,English Series 2005年第5期21卷 1071-1082页

作者： Shang Bin cui (Shangbin cui) Institute of Mathematics Sun Yat-Sen University Guangzhou 510275 P. R. China

In this paper, we study a free boundary problem arising from the modeling of tumor growth. The problem comprises two unknown functions： R = R（t）, the radius of the tumor, and u = u（r, t）, the concentration of nutrient in the tumor. The function u satisfies a nonlinear reaction diffusion equation in the region 0 〈 r 〈 R（t）, t 〉 0, and the function R satisfies a nonlinear integrodifferential equation containing u. Under some general conditions, we establish global existence of transient solutions, unique existence of a stationary solution, and convergence of transient solutions toward the stationary solution as t →∞.

关键词： Free boundary problem Tumor growth Global solution Asymptotic behavior

Y_(2)O_(3)弥散强化高速钢的激光选区熔化制备及性能

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工程科学学报 2025年第1期47卷 33-43页

作者：刘岩赵定国李月崔小杰王书桓薛月凯华北理工大学冶金与能源学院唐山063210

为提高高速钢的综合性能,利用行星式球磨机将M2高速钢(W_(6)Mo_(5)Cr_(4)V_(2))粉体与纳米尺寸的Y_(2)O_(3)颗粒进行低能球磨混合,并采用激光选区熔化制备Y_(2)O_(3)弥散强化M2高速钢.实验结果表明,球磨后的M2高速钢粉体基本呈球形,未... 详细信息

为提高高速钢的综合性能,利用行星式球磨机将M2高速钢(W_(6)Mo_(5)Cr_(4)V_(2))粉体与纳米尺寸的Y_(2)O_(3)颗粒进行低能球磨混合,并采用激光选区熔化制备Y_(2)O_(3)弥散强化M2高速钢.实验结果表明,球磨后的M2高速钢粉体基本呈球形,未发生严重变形,表面嵌布大量纳米级Y_(2)O_(3)颗粒.激光选区熔化成形的Y_(2)O_(3)弥散强化M2高速钢试样的致密度为98.3%,纵向微观组织主要为等轴晶和柱状枝晶,横向微观组织为等轴晶,平均晶粒尺寸为900 nm.X射线衍射结果显示Y_(2)O_(3)颗粒的加入对M2高速钢物相种类影响不大,仍由马氏体相、残余奥氏体相和碳化物组成.其抗拉强度达到了943 MPa,与未添加Y_(2)O_(3)颗粒的高速钢相比,强度提高了36%.

关键词：激光选区熔化 M2高速钢氧化物弥散强化激光电冶金力学性能