多楔带轮系的布置,计算和寿命分析

介绍了多楔带的结构及特点，结合多楔带在汽车发动机附件传动系中的应用，总结了多楔带传动轮系的布置设计方法和原则，分析了多楔带的静态张力、动态张力和寿命及其影响因素，给出了相应的计算公式。所有公式在小红族轿车系设计中得到了应用与验证，其中带长计算的程序化实践证明具有实用价值。     

AutoCAD国标化方法研究

本文对微机辅助绘图软件AutoCAD的国标化方法进行了研究,提出了一种利用“单位属性块”实现尺寸、公差自动标注的新方法,利用这种方法标注尺寸、公差易于控制和修改,且完全符合国标要求。     

CRCC认证业务的开展及体系的运行

根据《中华人民共和国产品认证认可条例》、CNAS认可规范、ISO导则65、铁路产品认证管理办法等文件的要求,在国家认监委和铁路产品认证管理委员会的领导下,积极稳妥地推进铁路产品认证工作,取得了可喜的成绩。     

快速公交系统通行能力计算方法研究

快速公交系统的通行能力是由瓶颈车站决定的.首先分析了车站通行能力的基本原理和主要影响因素,并基于排队论构造了单一停靠位通行能力的计算模型.同时,根据北京、杭州和昆明三地快速公交系统(公交专用道)的实际运营状况对模型参数进行了详细地标定和说明,提出缩短公交车平均停靠时间和改善系统运营稳定性是提升通行能力的重要途径.在此基础上,以北京市南中轴路快速公交为例,说明了模型的应用方法,并定量分析了各种因素对通行能力的影响.最后,对多停靠位车站的周转效率变化规律进行了分析,提出了其通行能力的计算方法.     

我国铁路铁矿石运输发展对策研究

随着运输结构调整的不断深入,"公转铁"运量持续增加,我国铁矿石运输发展对铁路货运增量具有重要意义.阐述我国铁矿石市场产需运现状,分析铁矿石铁路运输情况,针对当前铁路铁矿石运输存在的问题,提出我国铁路铁矿石运输发展对策措施,即:加强港口后方通道衔接,提高海铁联运比重;推进企业专用线建设,强化铁路"门到门"服务;积极推进"...     

Impact of vehicle usage on consumer choice of hybrid electric vehicles

We analyze the vehicle usage and consumer profile attributes extracted from both National Household Travel Survey and Vehicle Quality Survey data to understand the impact of vehicle usage upon consumers’ choices of hybrid electric vehicles in the US. In addition, the key characteristics of hybrid vehicle drivers are identified to determine the market segmentations of hybrid electric vehicles and the critical attributes to include in the choice model. After a compatibility test of two datasets, a pooled choice model combining both data sources illustrates the significant influences of vehicle usage upon consumers’ choices of hybrid electric vehicles. Even though the data-bases have in the past been used independently to study travel behavior and vehicle quality ratings, here we use them together.     

Accommodating preference heterogeneity in commuting mode choice: an empirical investigation in Shaoxing,China

A latent class model is developed to accommodate preference heterogeneity across commuters with respect to their mode choice between electric bike, private car, and public bus within the context of China. A three-segment solution – ‘electric bike individuals’, ‘private car addicts’, and ‘public bus enthusiasts’ – is identified, each characterized by heterogeneous preferences regarding specific mode attributes and unique socio-demographic profile. The choice model confirms the determinative effects of perceived alternative attributes on commuting mode choice, while the traditionally used objective attributes – travel time and cost – are found to have relatively small influences. The membership model provides solid explanations for these segment-specific preferences. This study provides a better understanding of the nature of mode choice behavior, which can be useful for strategies tailored to a specific segment in order to promote the use of sustainable transport modes.     

Are we doing it wrong or do we expect too much? Forces that push authorities to become public transport designers

This paper presents a number of reasons that are responsible for the disappointment of authorities in their operators’ efforts to develop public transport (PT) to the advantage of their travellers. The lessons drawn in this paper are based upon the competitive tendering experience of the authors and upon the results of meetings organised with parties involved in competitive tendering and aimed at exchanging lessons. There appears to be three main causes: (1) there is freedom for the operator, but the contract is bad; (2) there is freedom for the operator, there is a good contract, but there is no market; and (3) there is freedom for the operator, but the operator is not able to use it. The paper concludes with a few perspectives for improvement.     

适应汽车工业快速发展的科技档案管理与服务

在汽车工业快速发展的新形势下,产品科技档案管理的创新工作势在必行。文章阐述了改革创新产品科技档案的管理与服务方式和档案的管理与服务功能的重要措施。创新方式首先是管理要创新,其次是服务要创新。实现改革创新的措施就是要推进档案信息化建设,加强档案人员的培养与学习。这样,产品的科技档案管理才能适应形势的发展,才能使科技档案在产品开发中发挥更积极的作用。     

认真落实科学发展观努力提高公路交通网络的公共服务能力

文章全面部署“十一五”公路养护管理的各项工作任务,要求统一思想认识,明确工作目标,不断提高公共服务能力,“进一步完善公路网络,发挥路网整体效率”,推动公路养护管理工作再上新台阶。