系杆拱桥可靠性分析研究

结合工程实际，采用“JC法”进行系杆拱桥构件的可靠性计算。根据实际检测数据，考虑结构抗力和荷载的变化，计算当前结构构件的可靠性指标。考虑实际结构系统中，构件能力与荷载的相关性，确定结构系统比较合理的可靠性指标，完成当前结构承载能力的评估。     

现役水工钢闸门结构剩余寿命的预测

基于可靠性原理，确定了现役钢闸门结构构件最低可靠度设置标准．采用类比的方法确定了现役钢闸门结构可靠度评估时荷载的统计参数，建立了钢闸门结构构件抗力的衰减模型．在此基础上，提出了基于可靠度理论的现役钢闸门结构剩余寿命预测算法，并以受弯构件为例，对其剩余寿命进行了预测．结果表明，提出的方法在预测闸门构件剩余寿命时是有效的．     

海洋平台结构可靠性分析

为了延长近海洋平台的使用寿命，需要对现役平台结构进行了可靠性分析与评价，介绍了可靠性方法及其在近海平台极限状态设计和结构评价中的应用，给出了理论公式和实际计算方法。     

变量相关时悬臂桩支护结构可靠性分析

运用优化设计理论,提出了变量相关时结构可靠指标的新的计算方法．该方法将结构可靠指标β的计算转化为在等式约束条件（极限状态方程）下求目标函数（可靠指标表达式）的极小值问题,运用牛顿法迭代求解．作为算例,用该方法对在匀质土中的高层建筑深基坑悬臂桩支护结构进行了可靠性分析．     

现役结构模糊动态可靠度评估实用方法

针对现役结构特点,综合考虑了有关参数的随机性、结构失效准则的模糊性和抗力的时变性．提出了能使随时间变化的现役结构模糊动态可靠度复杂分析得到简化的实用评估过程,在阶段性评定上便于工程实际应用．文中计算了工程例题．     

改扩建工程的安全要求

在原有建筑基础上进行的改扩建工程,现役框架结构的安全问题一直都是工程考虑的重要问题。本文结合改扩建工程实际情况,系统性地运用理论知识分析了现役框架结构的可靠度,计算出其各个构件和整体框架结构的极限承载力的可靠性程度,确定荷载的概率分布、荷载效应组合的可靠性等级以及构件的安全等级。最后,结合中国国家博物馆的改扩建工程实例,对比分析现役框架结构的安全性,从而进一步了解如何对改扩建工程中现役框架结构的安全性进行精确评估。     

海洋平台结构可靠性分析

为了延长近海平台的使用寿命,需要对现役平台结构进行可靠性分析与评价．介绍了可靠性方法及其在近海平台极限状态设计和结构评价中的应用,给出了理论公式和实际计算方法．描述了ＦＳ１导管架海洋平台结构极限状态设计和结构评价时所考虑的三种失效情形：（１）平台失效;（２）甲板支腿失效;（３）基础失效．首先提出平台的非线性结构计算模型,然后确定作用在平台、甲板和过桥上的载荷,最后分析计算系统抗力和平台的可靠性．研究结果表明,当沉没深度达１０．６５ｍ时,平台失效概率达１／１０００．根据分析结果,提出了延长平台使用寿命的技术措施。本项目研究所采用的计算方法和研究成果可供类似结构分析和工程实践参考．     

珠江黄埔大桥斜拉桥主梁可靠度分析

作为斜拉桥结构主要承重构件的主梁,其可靠性关系到整个结构体系的安全.有限元可靠度方法对于大型复杂结构的可靠度分析有明显的优势,基于此方法研究珠江黄埔大桥斜拉桥的主梁可靠度并对其进行了敏感性分析.考虑几何非线性的影响,建立了基于有限元方法的斜拉桥主梁可靠度计算模型,通过对有限元列式直接微分的方法获得结构响应的梯度,采用一次可靠度方法计算可靠度指标,并根据计算结果直接对随机变量分布参数进行了敏感性分析.计算结果表明,该桥的主梁是足够安全的;布载方式对主梁可靠度有明显影响;主梁可靠度指标β对主梁的抗弯承载能力的均值和标准差最敏感.     

模糊优化方法在结构模糊可靠性分析中的应用

在结构可靠性分析中应用模糊集合理论，给出一般情况下结构失效的模糊定义，并导出计算可靠性指标的模糊优化问题，利用截集的概念转换成普通非线性参数规划问题，得到可靠性指标系列的模糊解．文中还根据模糊判决原理给出特征模糊可靠性指标的定义及计算方法，并给出了计算例题．     

曲线钢箱梁桥吊装施工稳定性分析及控制

曲线钢箱梁桥是在匝道桥中应用较为广泛的结构形式,此结构形式提高了工程项目在建设使用中的安全可靠性,但在吊装过程中,有多种因素会影响到桥梁结构的横向抗倾覆稳定性,各影响因素的影响规律、控制指标和标准尚未很好地解决。针对曲线钢箱梁桥吊装过程的稳定性,借鉴钢桥设计规范中抗倾覆稳定性计算分析方法,研究吊装过程的稳定性,提出吊装稳定系数,计算分析稳定系数与吊点位置、曲率半径、梁段长度、倾斜角度以及风荷载的相关性。结果表明：不同吊装方法对横向抗倾覆稳定性影响不同,横风对稳定系数影响较大,通过对比3种施工方案可知,纵桥向吊点间距建议取为梁段总长的2/3左右。在吊装过程中,尽量保持各吊点钢丝绳工作的同步性,避免节段发生倾斜;在超过六级风时,建议停止施工。     

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     

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