某电站核容器法兰三维瞬态密封分析

法兰密封失效是核压力容器的最基本失效形式之一，研究其密封性能具有十分重要的意义。针对电站核压力容器密封区域的改进结构，编写了有限元自动建模程序，应用核容器三维瞬态密封分析程序，对法兰密封系统进行了弹塑性接触分析和瞬态传热耦合计算，得到了各种工况下法兰的应力场、位移场和温度场。分析结果表明，电站核容器的法兰密封系统可以同时满足强度要求和密封要求；由于密封区斜面的存在，使密封面的接触区增大，接触压力分布更趋合理，并有助于减小内外槽的分离量。     

偏八辊轧机机架上横梁的三维有限元计算

本文在偏八辊冷轧机机架二维有限元分析的基础上,对上横梁部分利用线性静动力结构分析程序(SAP—5)在IBM—370计算机上,采用8—21可变节点等参元作了三维有限元分析,求得了上横梁在等效轧制力q作用下结构变形和应力变化情况,从而确定了结构的最大变形量和最薄弱部位,对改进机架结构设计具有一定参考价值。     

26m^2大型直线振动筛动应力计算分析

通过建立变参数多功能有限元计算模型，采用ＳＡＰ５结构分析程序对一种大型直线振动筛进行了动应力计算，计算结果与实测吻合，说明模型建立，载荷设置合理，这对该机型的改进设计具有指导意义。     

岩体动态响应分析程序的微机化及其应用

开发微机化的数值分析程序是推广数值方法在岩体工程中应用的一条有效途径。本文首先介绍一种微机数值分析程序的内存数据处理方法，然后介绍据此对岩体动态响应分析的二维非线性有限元程序ＤＹＮＰＡＫ的微机化改造和应用实例。     

采煤机螺旋滚筒的有限元分析

本文讨论采煤机螺旋滚筒的强度问题,用三角板单元编制了有限元程序SHEAR1,为了减少计算机内存和便于计算,采用了一维变带宽存储和网格自动生成。实测数据与计算结果基本一致。     

饱和土壤固结非线性有限元分析

为发展一个实用的土壤固结非线性有限元分析程序，在以往工作的基础上，以变分原理为基础，给出了饱和土壤固结弹塑性分析的基本方程．利用文中的理论，编制了有限元通用分析程序ＤＩＡＳＳ，并进行了例题计算．对考虑非线性弹性与弹粘塑性模型的土体固结分析方法进行了讨论．     

一种提高现有有限元求解器速度的方法

静力方程求解器是有限元分析程序的核心。随着求解规模的增大 ,求解器往往成为其工作的瓶颈。目前大量有限元程序采用的是一维变列高存储格式的直接法求解器 ,在这种求解器中引入循环展开 (loop- unrolling)技术以改进其工作性能。算例表明 ,求解速度得到很大提高。     

一类神经传导方程的修正的变网格有限元方法

研究了在神经传播过程中的一类非线性拟双曲方程的初边值问题．对二维情形应用常规变换，在常规的变网格有限元格式的基础上，提出了一种改进的变网格有限元格式，通过细致的分析和估计得到了最佳阶模误差估计结果，并使时间精度提高一阶．最后作了数值实验，说明方法是高效可行的．     

单调荷载下钢筋高强混凝土框架节点的非线性有限元分析

论述了单调荷载下分析、计算钢筋高强混凝土框架节点的非线性有限元方法 .针对高强混凝土选用基于等效单轴应变的增量式正交异性混凝土模型 ,高强混凝土单轴受力下的σ ε关系 .钢筋σ ε关系采用弹塑性模型及高强混凝土和钢筋之间采用双垂直弹簧模型 ,通过编制的二维非线性有限元分析程序计算了在单调荷载下的 4榀高强混凝土框架节点试件 ,计算结果与试验结果均吻合较好 .     

砷化镓金属—半导体场效应晶体管的二维数值分析

本文叙述用有限元方法对工作在导带的 GaAs MESFET's 器件进行二维稳态模拟的程序.用三角形单元不均匀网格剖分的程序,能局部加密,优化结点编码,缩小带宽;对基本方程离散采用改进的电荷浓缩法和有限元——有限差分混合法;方程求解采用藕合法,偏压步长大,计算速度快.     

Markedness and its Interpretation in Language Use

Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.     

低渗透非均质砂岩油藏启动压力梯度研究

理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。     

On Tragic Consciousness In The Works By Ernest Hemingway

As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.     

Achieving Unusual States of Matter Under High Pressure

正The periodicity of the elements and the non-reactivity of the inner-shell electrons are two related principles of chemistry,rooted in the atomic shell structure.Within compounds,Group I elements,for example,invariably assume the+1 oxidation state,and their chemical properties differ completely from those of the p-block elements.These general rules govern our understanding of chemical structures and reactions.Using first principles calcula-     

Exchange-Correlation and Electronic Excitation Energies from Pairing Matrix Fluctuations

We have developed an adiabatic connection to formulate the ground-state exchange-correlation energy in terms of pairing matrix linear fluctuations.This formulation of the exchange-correlation energy opens a new channel for density functional approximations based on the many-body perturbation theory.We illustrate the potential of such approaches with an approximation based on the particle-particle Random Phase Approximation(pp-RPA).This re-     

Density Functional Theory for the Response of Periodic Systems to Electric Fields Based on the Vector Potential Approach

正The electronic and nuclear(structural/vibrational)response of 1D-3D nanoscale systems to electric fields gives rise to a host of optical,mechanical,spectral,etc.properties that are of high theoretical and applied interest.Due to the computational difficulty of treating such large systems it is convenient to model them as infinite and periodic(at least,in first approximation).The fundamental theoretical/computational problem in doing so is that     

On the Thermodynamic Limit for Responses to Static Electromagnetic Fields

For molecular systems,the quantum-mechanical treatment of their responses to static electromagnetic fields usually employs a scalar-potential treatment of the electric field and a vector-potential treatment of the magnetic field.Although the potential for each field separately is associated with the choice of an(unphysical)origin,the precise choice of the origin for the electrostatic field has little consequences for the results.This is different for the     

An affordable accurate evaluation of the binding conformations predicted by molecular docking studies in bio-system

Franck-Condon factors bridge the gap between theoretical modeling and experimental observations for molecular electronic spectroscopy and electron transfer.Under the displaced harmonic oscillator approximation,multidimensional Franck-Condon factors are decomposed into a product of many one-dimensional(1D)Franck-Condon(FC)factors,and each 1D-FC factor is associated with one Huang-Rhys factor that determines the leading contribution of     

Call for Papers

<正>"The Journal of Shanghai Normal University:Mathematics"is published by Shanghai Normal University as regular issues of The Journal of Shanghai Normal University each year from 2014 in English.The editors-in-chief of the issues are professors Yuhao Cong and Maoan Han.The Journal of Shanghai Normal University was started in 1958 with     

Journal of Donghua University ( English Edition) Contents of Volume 31

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