静力凝聚法解叠层厚板的自由振动问题

文章提出一种改进的叠层板理论,并针对两种特殊的叠层和相应的边界条件,给出了叠层复合材料厚板的解析解.该文还应用静力凝聚法,凝聚掉平面内位移和转角自由度,这样,求解特征值问题的工作量将大大减少.算例表明,这些工作是相当有效的.     

双模量复合材料叠层矩形厚板的弯曲

本文应用加权残数法求解双模量复合材料叠层矩形厚板的弯曲问题。文中给出了两层十字叠层简支矩形厚板在正弦分布载荷作用下的中性面位置和挠度筹的数值结果。这些结果与精确解相当一致。这表明可将该法加以推广应用。     

无单元法在对称叠层板稳定问题中的应用

基于Kircihhoff板理论和移动最小二乘近似函数,进一步研究无单元Galerkin(EFGM)方法在对称叠层板稳定问题中的应用.分析中,本质边界条件采用罚因子法施加,对称叠层板的无单元法几何刚度矩阵由最小二乘法和变分原理得到.通过各向同性板和对称叠层板的数值算例及与其他方法的比较,表明采用EFGM法求解对称叠层板稳定问题具有收敛性好、精度高等一系列优点.     

n维爱因斯坦引力场中的真空曲率相关函数

从众所周知的爱因斯坦引力出发，以平坦的闽科夫斯基空间作为背景，使用度规张量的微扰展开式，根据Riemann曲率张量和Ricci曲率张量、旋转矩阵、曲率标量的定义，在弯曲的时空中计算了n维爱因斯坦引力的四种曲率两点真空相关函数的首项，得出了n维爱因斯坦引力的四种曲率两点真空相关函数的首项为零的结果。     

具有某种对称性质的正交多小波构造

当把尺度函数的滤波带看作标量滤波，其每一行具有对称、反对称性质时，能够构造具有类似性质的正交多小波．这里讨论的对称、反对称性质是不同于尺度函数和多小波的对称、反对称性质，此时尺度函数和多小波是不具有对称和反对称性质的．这里，仅考虑重数是3，同时矩阵滤波的长度是奇数的情况．     

电磁波场并矢格林函数的一种表达形式

提出了一种简化Maxwell方程组求解的新方法，应用这种新的方法可以方便地将无散矢势在M和N类矢量波函数空间中各分离成一个分量，每一个分量可以用一个标量函数来表示，然后再将无散矢势所满足的d’Alembert方程分解为两个标量的d’Alerobert方程，进而分析了无散矢势所满足的波动方程可以化为对一个标量d'Alerobert方程求解的方法，再分别用对应的标量格林函数来表示M和N类矢量波函数空间中的两个标量函数，并通过矢量微分运算求得电磁波场的并矢格林函数，这种方法无论对于电磁场的算子理论还是数值分析的方法，都有着非常重要的理论意义和应用价值。     

地基上复合材料叠层梁的稳定性

利用Ｈａｍｉｌｔｏｎ原理导出了复合材料叠层梁稳定性问题的控制方程和边界条件，并由此进一步导出了Ｗｉｎｋｌｅｒ－Ｐａｓｔｅｒｎａｋ地基上叠层梁稳定性问题的控制方程，其次，在不同的边界条件下，利用此控制方程获得了相应的屈曲载荷方程，并进行了具体的数值计算，同时讨论和分析了地基参数对屈曲载荷的影响，得到了一些很有价值的结论。     

无单元迦辽金法在对称叠层板屈曲问题中的应用

无单元法是一种新的数值算法,它信息处理简单,其基本思想是在计算域上用一些离散的点由最小二乘法来拟合场函数,从而摆脱单元的限制.因为它应用了滑动最小二乘法,所以与有限元不同,它的近似场函数不一定精确通过计算点,这会使计算稍趋复杂,但与这种方法带来的方便性相比,这点缺陷是微不足道的,因此这种方法愈来愈引起人们的关注.将无单元法用于对称叠层板的屈曲问题,通过计算不同边界条件下各向同性板和对称叠层板的屈曲荷载参数,验证了该法的有效性,且精度较高,有着广泛的工程应用前景.     

弹性地基上固支矩形中厚板弯曲问题的辛方法研究

利用Hellinger-Reissner二类变量广义变分原理,推导了弹性地基上中厚板弯曲问题的哈密顿求解体系,采用辛几何方法对全状态相变量进行分离变量,按本征函数展开法得到问题的辛本征通解.由于在求解过程中不需要事先人为选取挠度函数,而是从地基上中厚板弯曲的基本方程出发,直接利用数学方法求解,使得这类问题的求解更加合理...     

层合圆板与弹性地基相互作用分析

用半解析元法分析了轴对称横观各向同性层合圆厚板与弹性地基的相互作用，提出了一种新的半解析位移函数。采用在水平方向解析，在竖向进行离散化的方法，使动力相互作用问题化为一维数值计算问题，大大减少了计算工作量。数值计算结果表明：考虑相互作用后，层合圆板自振周期大于不考虑相互作用时的自振周期；在结构和地基动力相互作用分析中，地基的计算厚度可取为地基深度与基础的半径之比大于10，地基的计算面积可取在地基计算面积与基础面积之比大于30。     

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.     

Features of Women's language

Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women＇s language from these perspectives： pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women＇s language, more attention should be paid to language use in social context. What＇s more, the linguistic phenomena in a speaking community can be understood more thoroughly.     

An Analysis of Catherine＇s Character——Wuthering Heights

Wuthering Heights, Emily Bronte＇s only novel, was published in December of 1847 under the pseudonym Ellis Bell. The book did not gain immediate success, but it is now thought one of the finest novels in the English language. Catherine is the key character of this masterpiece, because everybody and everything center on her though she had a short life. We can understand this masterpiece better if we know Catherine well.     

Lower Paleozoic oil relationships within Williston Basin, Canada

The Williston Basin is a significant petroleum province, containing oil production zones that include the Middle Cambrian to Lower Ordovician, Upper Ordovician, Middle Devonian, Upper Devonian and Mississippian and within the Jurassic and Cretaceous. The oils of the Williston Basin exhibit a wide range of geochemical characteristics defined as "oil families", although the geochemical signature of the Cambrian Deadwood Formation and Lower Ordovician Winnipeg reservoired oils does not match any "oil family". Despite their close stratigraphic proximity, it is evident that the oils of the Lower Palaeozoic within the Williston Basin are distinct. This suggests the presence of a new "oil family" within the Williston Basin. Diagnostic geochemical signatures occur in the gasoline range chromatograms, within saturate fraction gas chromatograms and biomarker fingerprints. However, some of the established criteria and cross-plots that are currently used to segregate oils into distinct genetic families within the basin do not always meet with success, particularly when applied to the Lower Palaeozoic oils of the Deadwood and Winnipeg Formation.     

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     

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