Variable Cross-Section Rectangular Beam and Sensitivity Analysis for Lightweight Design of Bus Frame

Timoshenko beam element of variable cross-section rectangular tube is developed and applied in the lightweight design of bus frame in this paper. Firstly, the finite element formulations of variable cross-section beam (VCB) are derived under the loadsteps of axial deformation, torsional deformation and bending deformation. Secondly, bending deformation experiment and its detailed shell finite element model (FEM) simulation of variable cross-section rectangular tube were conducted; and the proposed VCB, detailed shell FEM and experimental results can be highly consistent. Thirdly, VCBs are used to substitute for parts of the uniform ones in a bus frame. An innovatively lightweight bus frame is obtained and all the performance responses are improved simultaneously. Finally, rollover analysis further shows the advantage of variable cross-section bus frame in crashworthiness design.     

基于离散梁模型的麦弗逊悬架减振器侧向力分析

本文以某A级车前悬架为例,建立了麦弗逊悬架多体动力学模型。在分析由于结构特点引起的减振器侧向力基础上,结合Adams宏命令建立了离散梁的C型螺旋弹簧模型。讨论了C型弹簧在不同曲率的中心线下的侧向力效果,并进行了仿真分析。对麦弗逊悬架减振器侧向力优化具有重要的意义。     

汕头LPG海底大型储气库工程预注浆堵水防渗技术

文章介绍了汕头LPG海底大型储气库工程中的预注浆堵水防渗技术,总结了预注浆具体施作的成功经验,可为今后类似工程施工提供借鉴.     

循环取货模式下入库道口车辆调度问题研究

在对汽车零部件物流循环取货模式及车辆调度问题分析的基础上,建立了零部件循环取货入库道口车辆调度问题的数学模型。在此基础上,用遗传算法对调度参数进行了优化。最后,通过实例计算验证了所设计的模型和算法的有效性和良好寻优性。     

拱桥阻滑板的原理及应用

拱桥作为一种最常用的桥梁型式,存在着拱脚水平推力较大的缺点,阻滑板体系能够克服此缺点。该文推导了阻滑板的水平抗推刚度,并结合一工程实例分析了影响阻滑板抗推刚度的因素,最后,提出了施工中应注意的事项。     

新能源车为谁而造?

<正>新能源车一直以来都是政策推动下的产物,而没有去真正适应市场的需求,中国的消费者热切希望车企能推出合适他们购买力与具有充电便利性的电动汽车,车企不应只迎合政策的鼓点去做华而不实的高价、高速与低魅力的电动车。这些年来,新能源车被有关政策高举高打,不断有各种推动政策出台鼓劲,各档财政补贴始终在诱惑车企和购车者,可市场反应以冷面相待,产销数字异常惨淡。新能源汽车唯政策驱动起于2009年终于2012年的声势浩大的新能源汽车"十城千辆"示范工程在财政补贴激励下还是黯然收     

突如其来的汽车业反垄断调查

<正>近期,政府将反垄断重锤砸向汽车业,致使许多进口汽车的车企纷纷降低整车及零部件维修价格。这场反垄断风波看似欲破除汽车行业反垄断现象,然而调查及处罚之突然令许多车企措手不及,也令外界惊讶。这场反垄断风波到底会带来何种影响还有待观察。"《反垄断法》看似高举轻放的重锤,体现了内外有别的客观现象,最大的用处是在对外经贸关系中作为一种与发达国家以及与跨国巨头智斗的法律武器。"2007年才出台的《反垄断法》从改革开放算起已经姗姗来迟,虽号称为经济宪     

浅谈武汉局推进信号专业化维修的几点体会

通过对既有维护模式的现状分析,引出推进信号专业化维修的必要性。系统介绍了武汉铁路局拓展专业修改革的举措,并阐述了推行信号专业修以来取得的效果和体会。     

Effects of different factors on drivers’ guidance compliance behaviors under road condition information shown on VMS

It is generally accepted that compliance behavior is affected by many factors. The purpose of this study is to investigate the effects of diverse factors on drivers’ guidance compliance behaviors under road condition information shown on graphic variable message sign (VMS), and based on this to find out a better information release mode. The involved data were obtained from questionnaire survey, and ordinal regression was used to analyze the casual relation between guidance compliance behavior and its influencing factors. Based on an overall analysis of conditions in driver’s route choice, an accurate method was proposed to calculate the compliance rate. The model testing information indicated that ordinal regression model with complementary log–log being the link function was appropriate to quantify the relation between the compliance rate and the factors. The estimation results showed that age, driving years, average annual mileage, monthly income, driving style, occupation, the degree of trust in VMS, the familiarity with road network and the route choice style were significant determinants of guidance compliance behavior. This paper also compared two different guidance modes which were ordinary guidance mode (M1) and predicted guidance mode (M2) through simulation. The average speed fluctuations and average travel time supported that M2 had better effect in improving traffic flow and balancing traffic load and resource. Some detailed suggestions of releasing guidance information were proposed with the explanation by flow-density curve and variation of traffic flows. These findings are the foundation to design and improve guidance systems by assessing guidance effect and modifying guidance algorithm.     

晕车影响因素及对策探讨

对晕车的传统研究认为晕车是视觉与平衡感官失衡造成矛盾引发的自我过度保护的后果。这个结论以及基于此结论开展的防治晕车措施已经持续了40余年。防治晕车的文献及市场上主流产品均以各种类型的晕车药物为主。本研究对现有晕车相关文献、专利、杂文等进行调查研究,总结分析出影响晕车主要因素为车内空气、车辆运动状态、视觉失衡、噪声、成员。使用对车辆乘员问卷调研的方法获取信息,对数据进行分析来研究晕车影响因素。数据表明晕车是一种发生频率高、普遍存在的乘车舒适性问题,具有明显的性别差异概率,是汽车行业发必须要面对和解决的重要问题之一。调查研究结果表明车内空气、车辆运动状态、视觉失衡三类诱发晕车的因素与文献研究结果一致。改善和防治晕车需要从车内空气、车辆运动状态、视觉失衡、噪声、成员这五类因素入手。使用车内空气的措施可以有效防治晕车现象的发生。清爽舒适的气味、降低温度、提高空气质量是三项有效的具体措施。