三维冲击—动力接触问题的有限元混合算法

提出了一种三维冲击－动力接触问题的有限元混合算法，该算法用库仑摩擦定律表述动力接触面的边界条件；按修正的Ｃｈｏｌｅｓｋｙ分解算法建立接触面的有效柔度阵方程。在按Ｎｅｗｍａｒｋ算法作逐步积分计算中，每一时间步的迭代计算，仅需反复求解接触面的有效柔度阵方程。     

动接触力法用于地下厂房结构震损过程分析

针对地下厂房衬砌与围岩的动力相互作用特点,提出了一种考虑接触面黏结特性的动接触力算法.该算法考虑了接触面间的黏结作用,可模拟计算动力作用下接触面的黏结接触、滑动接触和分离三种状态,适合地下厂房混凝土结构和围岩这种大型复杂接触系统动力计算.基于此接触面算法,采用自主开发的动力计算平台SUCED,对映秀湾水电站主厂房结构进行了动力分析.数值分析表明:考虑接触面粘结特性的动接触力算法是合理而有效的,计算结果揭示了地下厂房结构的震损演化过程与特点,为其抗震设计提供了理论依据.     

三维弹性接触问题有限元改进混合法及数值计算

本文提出了一种弹性接触问题有限元改进混合法,采用一种新的算法计算接触面柔度矩阵,用该方法对双齿啮合接触问题首次进行了三维弹性有限元计算。与混合法比较,改进混合法求解接触问题的计算效率有很大提高。     

空间多支管接头的局部柔性分析

本文用半解析法的计算机程序ＳＡＭＴＪ计算了多支管局部柔度阵的各元素，讨论了不受载支管的刚度效应和支管间的交互柔性，认为忽略这些效应将导致求得的支管接局部柔度为上界和下界，最后指出，在结构分析中用单支管的局部柔度替代多支管局部柔度将导致偏于危险的计算结果。     

不同地基模型下梁式基础的统一计算方法

通过对三弯矩方程解连续梁的方法在弹性地基梁计算上的扩展，提出了半无限大弹性体、有限压缩层和温克勒三种地基模型下梁式基础精确计算的新方法，使不同地基模型下梁式基础的计算达到了统一。文中推导得出了梁与地基共同工作的总柔度矩阵，建立了用力法计算弹性地基梁的统一方程。且给出了在不同地基模型下利用该方程计算地基梁时总柔度矩阵的构建方法，进而给出了采用本方法计算梁式基础的计算步骤。该算法可在任意基于地基是线弹性变形体假设的地基模型下使用。     

弹性枪架的等效刚度

该文他弹性枪架的等效刚度，为机枪系统合理的动力匹配提供必要的力学参数。用结构力学传递矩阵法建立了三维空间中一般变截面弱性梁变形的力学方程。以机枪正前方向射击为研究对象，取枪身与托架的联接处作为分析枪架刚度的特征点，应用柔度法分析枪架的弹性变形，由枪架的支承边界条件得到柔度方程，根据刚度与柔度的互逆关系得到了以６个参数描述的三自由度非正交广义弹簧系统。     

基于精细时程积分的结构动力响应降维分析

利用指数矩阵精细算法及状态方程直接积分法,讨论了求解动力响应问题的时程积分方式。通过选择代数精度高的Cotes积分,得出了计算精度非常高的动力响应结果。采用减缩主从自由度的精细时程积分算法对动力方程进行降维积分,通过保留指定的主自由度,删除其余的自由度来减小质量阵、阻尼阵和刚度阵的维数,既降低了指数矩阵的维数又保持了必要的计算精度,使指数矩阵分解所需时间大为降低。数值算例表明所给方法在保障求解精度的前提下具有很高的求解效率。     

基于两个矩阵方程的一种求逆速算法

基于两个矩阵方程，讨论了矩阵的一种快速求逆算法。在考虑矩阵的对称性，稀疏怀及减缩部分逆阵元素后，推导出逆阵块元素B11^-,B12^- 和B12^-的计算公式并给出算法程序实现方案与算例，是一种大幅减少计算机存贮量与计算次数的快速有效算法。     

桩-梁基础共同作用分析

考虑基础梁的刚度贡献、地基土对基础梁的支承作用，以及桩间土对桩的影响，建立桩-基础梁-地基土共同作用刚度方程．采用有限单元法建立整体分析模型，对其进行共同作用分析．将桩基受力情况分解为3种荷载工况的叠加，给出计算桩自身沉降量的计算公式(考虑了桩间土对相邻桩沉降的相互影响)．建立共同作用方程时，采用先通过计算柔度系数(沉降系数)形成柔度矩阵，由柔度矩阵求逆获得刚度矩阵的方法，使计算大为简化．     

结构对初始条件的动力响应的一种算法

从标准坐标变换方程出发，引入广义逆矩阵的求解方法，提出结构对初始条件的动力响应的一种新算法．这种算法回避开结构质量矩阵，以截断频率和对应的模态参数为输入，通过截断标准振型长方矩阵［Φ］的直接广义逆阵求解，求得结构对初始条件的动力响应．这一方法可用于已得到结构低阶模态参数而需进一步通过计算获得结构对初始条件的动力响应这一类工程中实际存在的问题．算例表明，精度满足工程要求．     

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.     

Design and analysis of generic LBS application developing platform

Location based services is promising due to its novel working style and contents.A software platform is proposed to provide application programs of typical location based services and support new applications developing efficiently. The analysis shows that this scheme is easy implemented, low cost and adapt to all kinds of mobile nework system.     

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