复合材料斜交网格机身结构

该文介绍了斜交网格结构,包括这种结构的诞生、特点和发展历史.回顾了民用飞机机身典型的结构形式,对刚架结构、硬壳式结构、半硬壳式机身结构形式作了简要介绍和分析.论述了斜交网格结构在航天和航空领域的应用情况,以及目前国际上运用复合材料斜交网格结构所取得的进展.将复合材料斜交网格结构与传统结构进行了对比分析,给出了复合材料斜交网格结构所具有的潜在结构优势.最后在对比分析的基础上,对这种结构在复合材料机身上的应用前景进行了探讨.     

全自动液压压砖机机身结构有限元模态分析

用Pro/Engineer对全自动液压压砖机机身进行了有限元模态分析.通过对压砖机的受力状况简化及对三维有限元模型的模拟计算,得了到静态载荷下压砖机机身的前六阶固有频率及相应的固有振型等动态特性参数,并对每阶振型进行了详细地分析和评价.这对于了解压砖机的结构特性并进而改善其性能将具有一定的意义,并可为全自动液压压砖机的整体设计提供理论依据.     

基于ISIGHT的复合材料机身优化设计研究

对机身等直段受气密载荷作用时蒙皮铺层的优化设计进行初步研究。将有限元软件NASTRAN求解器与遗传算法相结合,通过ISIGHT软件实现具体流程,并通过C++编程弥补ISIGHT的不足。分析得出了在气密载荷作用下,最优的机身等直段蒙皮的铺层顺序、铺层角度和层数。将优化前后复合材料机身对比,机身等值段减轻了16.2%的机身结构重量;与A320-200金属机身对比,相应机身段减轻了26.5%,提高了结构效率。该方法可实现读取初值、计算和读取结果整个过程的自动化,减少了大量计算时间。     

制冷组件安装区域温度场分析研究及影响

现代民用科技机身结构大量的采用了复合材料,复合材料遇到高温时会变软,耐热性较差,对复合材料周围的环境温度提出了新的要求。本文以某型飞机的制冷组件安装区域进行温度场CFD计算,分析了安装区内的高温部件对机身复合材料结构的影响。为了防止机身复合材料被高温部件烫伤,在高温部件的上方安装隔热板同时进行局部通风冷却,并对相应的工况进行CFD计算对比。     

液压机机身强度和刚度计算与分析

文章通过对RZU800HA和YH20-200液压机机身的强度和刚度的有限元分析计算,扼要地介绍了按照不同的工况给实体模型加载,求得应力集中区关键点处的应力应变值,在此基础上进行结构优化的过程,使得既减轻了机身质量又提高了强度和刚度,并设计出一种新型的无腹板结构的单柱机身,改变了腹板为主承力板、单柱机身只能是小喉深的传统观念,拓展了液压机的应用领域,具有很好的实用价值.     

框架式油压机整板焊接机身的合理设计

机身作为油压机主要零部件的安装基础,承受着工作中的全部载荷,因此机身设计的好坏对整机的使用性能、制造工艺性及生产成本均有很重要的意义。框架式油压机是一类用途广泛的油压机,其机身的结构要依据主缸工作力、工作台面的大小等不同而优化设计,并要合理地进行强度计算与校核,还可以采用先进的有限元方法进行应力和位移分析。     

用多肢体化实现步行机器人的自位机能

实现自位功能是改良非结构环境下步行机器人运行性能和提高其自主行走能力的共性问题，本人多肢体化的角度对步行机器人的自位问题进行了探讨，阐述了具有自位能力的步行机器人的最少机身杆件数和机身杆件间的合理自由度配置方案，分析了机身杆件与腿机构协同工作时的自位行为过程，提出了一处具有自位机能的三肢体六足步行机器人模型。     

基于ABAQUS有限元的110 t折弯机结构优化

针对工作载荷为110 t型折弯机的加工精度不足和主要性能指标较差等缺陷,应用ABAQUS有限元软件对110 t折弯机进行分析与优化设计.通过分析机身中工作台和侧板的强度与刚度,解决机身过度变形导致的工件精度低下的问题,并根据滑块竖直方向的变形曲线优化设计机械补偿装置的结构.有限元分析结果显示,优化后机身质量仅增加188...     

对击式液压模锻锤机身静态有限元分析

通过应用有限元ANSYS软件对25KJ对击式液压模锻锤机身的应力和应变分析。验证了机身几何模型和力学模型的可靠性，为设备的进一步结构优化和设计改造提供了前提条件。     

10 MN弹性成形压机结构分析与优化

文章主要针对10MN弹性成形压机机身刚强度进行计算分析。首先,在SolidWorks中建立液压机的三维整机模型,并对原机架进行结构改进,得出对比机型;然后,应用ANSYS有限元分析软件完成2种模型的静力分析、模态分析,得出它们的应力和应变分布云图、前6阶固有频率和相应振型;最后,在改进模型的基础上,采用响应曲面优化分析的方法,以机身质量最小化、一阶固有频率最大化的权衡量为设计目标进行结构尺寸优化。分析结果表明,改进模型的最大形变、应变、应力均有所减小,结构稳定性得到提升,振幅偏小、高阶频率的激励对其振动的影响也不大。     

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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