空间钢网格盒式筒中筒结构地震弹塑性响应分析

为研究空间钢网格盒式筒中筒结构在地震作用下的弹塑性性能,利用有限元软件MIDAS建立结构数值模型,对其进行罕遇地震作用下弹性时程分析和弹塑性时程分析,并对结构顶点位移时程曲线、基底剪力时程曲线、楼层位移角等进行比较分析.通过结构弹塑性反应分析得到结构塑性铰损伤过程,得出该结构塑性铰发展及构件屈服顺序.结果表明:盒式筒中筒结构抗震防线明确,能够很好地实现基于性能的结构设计.     

变截面高层筒中筒结构传递矩阵法

提出了一种分析高层变截面筒中筒结构的传递矩阵法,这是一种简化的计算方法,能快速地计算水平荷载下整体水平位移,位外筒的内力,由算例看出,这种方法可获得满意的效果,由这一方法,进而还可方便地进行整体动力特性,弹性时程和结构优化分析等。     

基于风力机整机气弹稳定性的塔筒结构优化

基于风力机整机的稳定性,提出了一种研究风力机塔筒结构优化的新方法。该方法以减小系统振动为目标函数,塔筒的直径和壁厚为优化参数,通过强度、变形量及质量等作为约束条件建立优化模型,利用内点惩罚函数法求解此优化问题,最后运用坎贝尔图(Campbell图)对叶片与塔筒耦合的风力机整机系统的稳定性进行分析。应用此方法对某2 MW水平轴风力机塔筒结构进行优化,整机的稳定性能得到很大改善,塔筒质量减少13%,具有一定的理论和工程实用价值。     

矩形筒中筒结构动力特性的简化分析

导出了截面含双对称轴的矩形筒中筒单元的刚度矩阵，这可使框筒和筒中筒结构的动力特性分析大大简化。计算表明：文中方法具有较高的计算精度和效率。     

高层筒中筒结构的整体稳定简化分析

按照常规的方法,将筒中筒结构的外框筒连续化为具有弯曲变形和剪切变形,同时考虑其剪力滞后影响的等效实腹筒体．内筒只考虑其弯曲变形,内外筒的变形是协调的．然后用虚拟水平分布荷载来模拟由竖向荷载产生的Ｐ＿Δ效应,推导出结构的整体稳定微分方程,用Ｇａｌｅｒｋｉｎ法求解方程并获得整体结构的最小临界荷载．     

高层筒中筒结构的整体稳定分析

将筒中筒结构的外框筒视为具有弯曲变形和剪切变形，并受剪力滞后影响的等效实腹筒体，视内筒只受弯曲变形。根据内外筒的变形协调条件，建立了整体结构稳定微分方程，用Ｇａｌｅｒｋｉｎ法求解方程并获得了整体结构的最小临界荷载。     

高层筒中筒结构的二阶分析

本文提出了高层筒中筒结构的一种二阶分析方法．首先按Ｃｏｕｌ．Ａ的方法将筒中筒结构的外框筒连续化为具有弯曲变形和剪切变形,同时考虑其剪力滞后影响的等效实腹筒体,内筒只考虑其弯曲变形．然后用虚拟水平分布荷载来模拟由竖向荷载产生的二阶效应,根据内外筒的变形协调条件,导出筒中筒结构二阶分析的五阶常微分方程．最后采用有限差分法进行数值求解．     

高层筒中筒结构协同分析的状态空间法

将状态空间方法引入筒中筒结构的协同分析中,在结构连续化假定的基础上,建立起结构的状态空间方程.即采用连续化模型,用空间坐标模拟时间坐标,导出筒中筒结构协同分析的状态空间表达式,进而用精细积分法求出问题的高精度数值解.提出一套分析筒中筒结构协同工作的方法,对筒中筒结构进行协同计算,将所要解决的边值问题转化为初值问题,进而用Matlab编程求解.最后,通过实例给予验证.     

高层框筒和筒中筒结构动力特性的简化分析

用连续－离散化方法分析高层建筑筒体结构的动力特性，在导出的等效筒体层间段单元的刚度矩阵中，所采用的位移函数能反映筒体结构的剪力滞后效应，采用筒体的这种等效单元和刚性楼面及结构质量集中于楼面的假定，可使筒体结构的动力特性分析大大简化，与有限单元法比较，具有计算简捷和应用方便的优点，计算表明，该方法具有较高的精度和效率。     

涂装油缸清洗机喷淋清洗筒结构的设计

以涂装油缸为实验对象,根据涂装油缸清洗机喷淋清洗筒自身的结构特点,分析油缸在进行涂装之前受污染的主要原因。从清洗机设备的工作原理入手,找出原有设备在清洗油缸工件时因喷淋清洗筒结构设计的不合理,导致对油缸工件表面清洗不彻底、喷淋清洗后无法及时进行干燥等问题。通过改进设计清洗机喷淋清洗筒内外部分的结构、合理优化喷淋清洗筒的相关参数来解决上述存在的问题,使涂装油缸的清洗质量和效率得到显著提高。     

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.     

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     

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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