车架结构对微型客车碰撞能量分布的影响研究

本文以Lagrange法为算法为基础，采用动态显式非线性有限元分析技术，就车架结构对微型客车碰撞能量分布的影响特性进行了捞真研究。探讨了关键部件的建模处理及整车仿真参数设置与控制方法，妥善处理了仿真精度和计算效率的矛盾，实现了用较少的单元和镎短的时间对微小型客车正面碰撞的模拟。在此基础上，本文以添加第一横梁、第三横梁和保险杠前后的碰撞为例，对车架结构对微型客车碰撞能量分布的影响进行了仿真研究。模拟结果表明，第三横梁和保险杠对微型小客车的耐撞性起重要的作用，添加第三横梁和保险杠后，微型小客车正面碰撞时，碰撞能量分散较快，其纵梁前段和驾驶员座位下与前门槛板对应的纵梁部分基本未发生变形，整车的耐撞性得到了明显的改善 。     

管架式轿车车身碰撞仿真分析

通过对自主设计的管架式轿车车身建模，利用非线性CAE（计算机辅助工程）工具对车身正面碰撞过程进行了仿真分析，得出了变形和主要碰撞参数的时间特性，并根据仿真结果对管架结构进行了局部优化和改进。结果表明，这种新型轿车车身能满足汽车碰撞安全法规的要求。     

微型客车的碰撞安全性设计与改进技术研究

针对微型客车的碰撞安全性现状,提出了微型客车的碰撞安全性设计与改进策略,探讨了综合利用CAE技术与碰撞试验技术进行微型客车碰撞安全性优化设计的可行性,提出了微型客车碰撞安全性设计与改进的基本步骤．解决了微型客车新产品N1的安全性设计问题和微型客车老产品X477的碰撞安全性改进问题,这两个产品是国内最先开发成功的、完全依靠国内技术达到我国汽车正面碰撞安全法规要求的产品．     

小型客车整车正面碰撞分析

应用动态非线性有限元法对小型客车整车在正面碰撞过程中的大变形过程进行了计算机模拟 运用ANSYS/LS -DYNA3D软件 ,在合理简化的基础上 ,建立了整车的有限元模型 通过计算机模拟 ,预测了某小型客车在正面碰撞过程中的变形位置和变形形式 模拟结果表明 ,碰撞过程为 50ms,撞击力达到 85G ,最大位移 3 0cm ,乘客门产生了较大变形 ,该车的前部结构耐撞性较差 针对存在的问题 ,对车辆结构提出了改进措施 此外 ,通过对比分析发现 :整体碰撞结果与部件碰撞相差较远 ,受撞部件的塌陷模式和对碰撞能量的吸收都有很大区别 最后以车架为重点进行了探索性改进 模拟表明 ,对车辆前部进行适当削弱可以有效地改善汽车耐撞性 ,但需对整体做较大改动才能彻底改善汽车的耐撞性     

车辆碰撞计算机模拟分析与评价

针对某型轿车进行了正面和侧面碰撞计算机模拟分析与评价.建立了含50百分位的HybridⅢ型假人及安全带约束系统的整车有限元模型,根据动态非线性有限元法的基本原理,建立碰撞过程描述方程和结构有限元离散化方程.在LS-DYNA环境下,对整车集成系统进行了正面和侧面碰撞的数值模拟和分析,求解出了碰撞时整车位移、速度和加速时间,并分析了该车在碰撞过程中主要吸能部件的吸能效果及能量与力的传播途径,以及假人的伤害程度.仿真结果表明,含假人的汽车碰撞过程计算机模拟,不仅能预测汽车结构本身的耐撞性能,还能较准确地预测碰撞过程中乘员的响应与伤害程度,对于减少实车碰撞试验次数,加快新车型开发速度具有重要意义.     

小型客车车架前纵梁碰撞性能的模拟仿真

为了改进小型客车正碰撞性能,建立了小型客车车架前纵梁碰撞的有限元模型.利用ABAQUS软件中显示积分算法模块对小型客车做了正面碰撞刚性墙的碰撞仿真试验.得出了对所设计的前纵梁在不同截面形状、不同材料以及不同厚度等设计方案,在不同车速下前纵梁碰撞变形和吸能效果的仿真实验结果,最后从中选出好的设计方案.前纵梁碰撞性能模拟仿真试验表明,运用该软件模拟汽车零部件碰撞,优化设计方案是可行的.     

燃油车改制电动车后正面碰撞性能变化分析

在中国汽车市场由传统燃油车向新能源车的转变过程中,各车企开始着手研发电动车,大部分车企选择由传统燃油车改制为电动车,而改制电动汽车的碰撞安全显得尤为重要。本文研究了电动车开发过程中车辆改制前后正面碰撞性能的变化趋势,对原车及其改制车的正面碰撞主要性能指标进行了对比分析,并通过整车变形、速度及加速度变化,总结了传统燃油车改制电动车正面碰撞性能的主要影响因素及变化趋势,为今后开发电动车提供了借鉴和参考。同时,结合计算机辅助工程(CAE)仿真分析方法与试验,可以快速地验证电动车改制方案,确保电动车满足国家碰撞安全法规GB11551-2014《汽车正面碰撞的乘员保护》标准。     

车辆正面碰撞的仿真与试验

以某轿车为对象,建立含乘员约束系统整车有限元模型.在LS-DYNA环境下,将整个模型划分为36万个壳单元进行正面碰撞过程数值模拟.对碰撞过程中能量转移、耗散、主要结构的吸能效果、乘驾假人的变形损伤指标进行了分析.将仿真分析结果与碰撞试验测试结果进行对比和评估,验证了含乘员约束系统的整车有限元模型的有效性;含乘员约束系统的汽车碰撞模型及计算机仿真分析方法较真实地反映出实车碰撞的状况和结果,具有实际工程应用价值.     

汽车碰撞时间特性的仿真

随着汽车向高速化方向发展,对汽车的安全性要求越来越高,汽车在高速下的碰撞特性研究也就显得非常重要。文中讨论了汽车碰撞时车体的加速度、速度和位移的变化情况,给出了用于仿真研究的碰撞参数模型,并对汽车正面碰撞时车体的时间特性（加速度、速度）进行了仿真分析。     

基于HyperMesh的6125型大客车正碰安全性研究

以6125型客车为研究对象,利用CATIA软件对该型客车车身骨架进行建模,通过HyperMesh软件进行网格划分,建立有限元模型,应用非线性有限元软件LSDYNA对该客车有限元模型进行正面碰撞仿真计算。参照欧盟ECE R94《正面碰撞乘员保护》标准和美国FMVSS208《碰撞的乘员保护》标准中对碰撞的变形和碰撞安全性的要求,提出增加前段地板骨架及车架(司机地板区域)纵梁厚度以及增加前围保险杠和吸能盒的改进方案。结果表明,该优化方案达到了行业标准的要求,可为大客车碰撞事故分析及改进提供参考。     

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