两对边简支的矩形板横向自由振动的解析解

将弹性点支反力视为作用于板上的待定外力 ,求得了两对边简支而另两对边为任意支承的矩形板横向振动的解析解。利用弹性点支处挠度与该处的待定外力之间的关系 ,得到了一个用阶数等于弹性点支个数的行列式来表示的频率方程 ,并给出了一个数值算例。     

两对边简支的矩形板横向自由振动的解析解

将弹性点支反力视为作用于板上的待定外力,求得了两对边简支而另两对边为任意支承的矩形板横向振动的解析解。利用弹性点支处挠度与该处的待定外力之间的关系。得到了一个用阶数等于弹性点支个数的行列式来表示的频率方程,并给出了一个数值算例。     

环形肋板动反力分析

基于弹性波传播理论和板的弯曲振动方程，分析了环形薄板的伸缩振动和弯曲振动的特性，推导了与边界位移，振动频率有关动反力的方程，并计算了径向动反力随周向波数ｎ和振动频率变化的趋势。     

环形肋板动反力分析

基于弹性波传播理论和板的弯曲振动方程，分析了环形薄板的伸缩振动和弯曲振动的特性，推导了与边界位移、振动频率有关动反力的方程，并计算了径向动反力随周向波数ｎ和振动频率变化的趋势．     

流场中有限长纵横加筋圆柱壳声辐射

研究流场中加环肋和纵骨的有限长圆柱壳在简谐径向点激励下的声辐射。把环肋和纵骨等价为线反力和反力矩作用在柱壳内壁,将反力和反力矩表示成位移的函数。基于Ｆｌｕｅｇｇｅ薄壳理论,推导了流体的流固耦合振动方程,计算了其表面振动速度级和辐射声功率级。     

求解旋转板、壳振动问题的半解析有限元分析

根据小变形弹性理论,用有限棱柱法解决了旋转板、壳自由振动的问题·通过分析旋转板、壳被分成若干个半解析的环形棱柱单元,位移函数采用环向为解析的三角级数而径向和轴向为离散的插值函数,推导出刚度和质量矩阵,计算了板、壳实例,并与实验值作了对比,得到了很好的结果     

简谐激励下多跨连续梁振动问题的解析解

本文把多跨连续梁按单跨梁处理，将中间支座反力视为作用在梁上的未知外力，给出简谐激励下多跨连续梁动位移的解析式，同时还给出了自由振动的频率方程和振型函数的统一解析式，比已有的方法更为简单实用。     

在均布载荷作用下,双列柱支承的条形无限板的计算

具有四边自由,两列柱距为l,每列柱距为2a,悬臂长度为b的条形长板,在均布载荷q作用下的内力矩解析表达式是写不出的。但是,如果沿长度x方面视为无限板来处理,此问题可由下列三种情况的解析解相叠加而得出: 1.在均布载荷作用下两边为简支承的悬臂板,其内力矩可按简形板弯曲内力公式计算; 2.在上列柱的位置上只承受集中反力和一条负线布反力; 3.在下列柱的位置上只承受集中反力和一条负线布反力; 根据圣文南原理,远处边界对本边界影响小的道理,对情况2可看成只有上面自由边界,而下面边界可视为无限远。对情况3也同样处理。于是,这种问题可用复…     

厚度变化对中厚环形板非线性振动的影响

对变厚度中厚环板的非线性振动问题进行了讨论,采用半解析法及罚函数法,得到了在不同边界条件下,厚度变化对非线性振动基频的影响曲线图及最佳的厚度分布图．     

粘弹性基支薄板的准静态弯曲

本文讨论粘弹性基础上的粘弹薄板准静态弯曲的一般解法.文中利用板-地基系统的弹性粘弹性相应原理,以对边简支、另两边自由的粘弹性基支矩形板为例,导出了在拉氏象空间中的有关算式,然后采用数值逆变换的方法,求得板的挠度、基支反力和内力.数值计算中,同时给出了粘弹基支的弹性板、弹性基支的粘弹板和非基支粘弹性薄板的各种解答.     

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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