发动机无法启动常见故障分析

每一台汽油发动机的启动和运转均需要火花、燃油和压缩。当发动机不启动时,有计划的诊断步骤将帮助我们迅速确定故障的原因。本文中,将说明如何采取有计划的诊断步骤对发动机无法启动的故障进行诊断,并将解释为什么围绕基本的因素能使故障诊断工作完成得更快。汽油发动机的故障及诊断方法为:1.起动电路对于不启动故障的诊断一般总是从起动电路开始。一般的起动电路主要由蓄电池、起动机和电缆组成,这里只介绍蓄电池故障检测。蓄电池故障将是任何不启动诊断的首检目标。在启动发动机期间,蓄电池的电压是一重要因素。若蓄电池电压下降过低,则使电燃油泵不能达到最佳速度,从而使燃油传送减少;另一方面,下降过低的蓄电池电压,将影响发动机控制模块,该模块进而导致无火花、不传送燃油或导     

汽车实际应用中的节能措施

汽车出厂时,其燃油经济性基本已经被确定,本文从满足广大汽车使用者希望在现有的车辆上降低油耗、节约使用成本的角度,提出相关的节能措施,主要从操作技术(如发动机起动、汽车起步加速、换档变速及车速控制、升温及保温、汽车滑行等)和节能产品的选用及日常维护三方面进行了探讨。     

汽车电气系统寄生电流的检测与控制

汽车在日常使用和维修中能使电子元件、控制模块性能会下降,线路的各个插接件之间会产生松动等。这都能使汽车电气系统的寄生电流增加,造成蓄电池损坏和火灾的危险性。所以经常检测电气系统的寄生电流尤为重要。     

车用蓄电池快速充电技术分析

本文通过对当前动力电池优缺点的分析,提出我国应该增加投资力度,引进国外已经攻克蓄电池缺点的最新研究成果,并通过我国科技工作者的技术攻关,解决驱动汽车的动力电池充电时间长、使用寿命短,消费者不满意的问题。于此同时,也不放弃对其他种类的电力汽车的研究。     

基于ADVISOR的并联混动汽车控制策略再开发研究

控制策略开发作为混合动力汽车的核心技术之一,成为了国内外研究的热点。合理的控制策略和方法,对于驱动车辆在不同工况下行驶具有重要意义。本文通过使用ADVISOR软件对并联式混动汽车的控制策略进行再开发,提高工作模式切换的合理性,改善电动机对蓄电池组的充放电性能,提高车辆的续航能力,对于混动汽车的发展具有重要的意义。     

奇瑞A3安全气囊灯常亮故障分析与排除

汽车安全装备主要包括安全带、防撞式车身和安全气囊防护系统（SRS）等，为了在短暂时间里减轻对乘员的伤害，安全气囊系统通信应用了具有通信速度快、可靠性高等优点的CANBUS系统。当安全气囊系统发生故障时，必须及时到维修站将故障排除，以保证行车安全。     

地铁机电设备蓄电池性能比较及应用研究

为合理选用地铁机电设备蓄电池,减少备品备件投资,在分析地铁各机电设备蓄电池容量及分布基础上,介绍其常用蓄电池的分类、结构及原理,重点比较了胶体电池、常规铅酸电池（AGM蓄电池）、锂电池的结构与性能参数及差异,提出了经济效益比较、各地应用情况统计、选用指导建议,以期为地铁机电设备蓄电池技术的标准统一、选用方面提供借鉴。     

汽车巡航系统的使用和发展方向

汽车巡航系统在中高档轿车上的应用日益广泛,对汽车的驾驶舒适性、安全性、经济性起到了重要的作用。介绍汽车巡航系统的优点、主要功能和使用方法,并对新型汽车巡航系统的发展动向作了简要的阐述。     

五箭齐发:细分市场的百步穿杨——大金龙五款新车亮相2012北京道路运输展

"在当前竞争日益激烈的汽车市场上,企业的核心竞争力必须以科技创新作为支撑,技术强者赢,能力强者胜。"大金龙总经理郭仁祥笃信,孜孜不倦追求一骑绝尘的企业,科技创新乃制胜法宝。有着相同看法的,还有郭仁祥的搭档——大金龙副总     

占领未来智高点? 看金旅背后智能网联版图大幕开启

正近年来,全球汽车产业加速向电动、智能、互联发展,大数据技术已成为未来新能源汽车的核心关键技术之一。8月21日,在这个凤凰花开的季节里,新能源汽车国家大数据联盟(以下简称"大数据联盟")2018年中会议暨新能源汽车评价指数研讨会在美丽的花园城市厦门隆重召开。"中国工况"提升大数据价值据悉,大数据联盟是由新能源汽车国家监测与管理中心,以及包括金旅客车在内的新能源汽车制造商、零部件供     

Analysis of factors affecting the choice of route of pedestrians

Pedestrians as compared to vehicular traffic enjoy a high degree freedom of movement even in heavily congested areas. Consequently, there are more alternative links available to pedestrians between a given origin‐destination (O‐D) pair. This paper describes a study done by the University of Calgary to evaluate the factors affecting the choice of route on intra‐CBD trips or trips within the Central Business District (CBD).

An origin destination survey conducted in downtown Calgary, Alberta enabled the identification of the most significant factors influencing the choice. These factors were analyzed in relation to the physical characteristics of the location, personal characteristics of the trip maker and the type of the trip.

It appears that most people chose the shortest link and factors such as the level of congestion, safety or visual attractions were only secondary. This suggests that the length should be made a major consideration when planning and designing pedestrian links.     

输油管道中原油乳状液的流变性研究

原油乳状液的流变性是原油开采后在管道中输送的重要研究方面,为了更好地研究这一性质,采用电动搅拌机、偏光显微镜以及流变仪等仪器来测定不同含水率的原油乳状液在不同条件下的黏度,观测不同含水率的原油乳状液在偏光显微镜下的形态。并且分别对原油乳状液的黏度与含水率之间的关系以及与剪切速率之间的关系进行研究,初步确定了所测区块原油乳状液的转相点以及该区块原油乳状液的流变特性,为生产中的油气集输提供了理论依据。     

Preliminary results of an analysis of areas of influence in Shanghai

The main deficiency of most current modeling approaches to transportation can be identified as neglect of the integration of existing geographical knowledge in regard to the ex ante transport/land use modeling approaches, with its focus on territorial dynamics and theory development. This paper addresses this aspect of the problem by introducing a theoretical and methodological framework for the analysis of the interrelationship between land uses. The analysis attempts to determine to what extent the functional land use in a city can be considered an ordered pattern. The order sought does not rely on purely spatial configurations, but on the correlation of transportation and land use. The first section of this paper focuses on theoretical considerations. It stresses the fact that conventional approaches do not apply in the present context. It then suggests an alternative based on areas of influence and measured in terms of level of attractance of land uses. The second describes a procedure based on this alternative following the remarkable contribution of Hanjoul, Beguin and Thill. An application of this procedure to the analysis of Shanghai is then examined. Finally, an evaluation of the strategies for optimizing the interrelationship between land uses is presented. The paper concludes with a possible research agenda.     

埋地管道防腐保温层失效评价

明确埋地管道防腐保温层的技术评价标准,对埋地钢质管道的安全运行,延长管道使用寿命具有重要意义。为了对埋地管道防腐保温层做出有效评价,从间接检测与开挖检测2个方面,结合现场检测数据,提出了基于防腐保温层的电流衰减率、绝缘电阻率、质量状况与厚度的分级评价标准及基于4种评价指标的综合评判方法。工程实践表明,该评价标准对防腐保温层是否存在失效能做出有效判断。     

城市轨道交通杂散电流监测系统概述

介绍了城市轨道交通工程中杂散电流不同的监测系统的构成,分析了集中式、分散式和智能型等监测系统的配置和功能,以及智能型实时在线监测系统的重要意义,为轨道交通工程杂散电流监测系统的选择与应用提供参考。     

实现多组态计量软件集中监控的可行性分析

天然气自动计量系统有多种组态软件,由于软件的不相通性,造成了计量系统数据采集的通用性差、数据传输与入库的时效性差、数据利用的可靠性低.结合各组态软件的实际情况,从设计上充分利用Oracle大数据处理能力以及Partition(分区表)的特性,实现历史数据的存储,应用WebService与COM+数据访问组件提供多层数据访问架构,采用OPC与DDE工业数据交换协议,实现了各站场计量数据的实时上传,为连续数据采集和实时监控提供了可能,节约了改造成本.     

注汽管道承压能力评估和实物试验验证

基于失效评估图技术对某注汽管道进行了承压能力评价,给出了管线在不同腐蚀壁厚情况下的极限承压能力和极限裂纹尺寸。并利用实物爆破试验验证了评价方法的安全性和有效性,通过对爆破断口进行宏观和微观分析,发现管段的开裂属于脆性开裂。     

Non-parametric analyses of efficiency of airports

This paper estimates the efficiencies and productivity changes of 12 international airports in the Asia-Pacific region based on data from 1998 to 2006. We apply stochastic frontier analysis (SFA) to compute efficiency estimates and use the Malmquist productivity index (MPI) to analyze productivity changes. We use the SFA model with a translog-type production function after testing the statistical hypotheses. According to the results of the SFA hypothesis tests, airports have experienced a technological regression; the deviations from the efficiency frontier are caused more by technical inefficiency than random noise. However, the inefficiency was found to decrease. The MPI reveals a declining trend resulting more from technological change than from efficiency change, with a decrease in inefficiency. Taken together, both the hypothesis tests and the MPI not only provide consistent conclusions, but also suggest that airports should concentrate on technological progress.     

波纹管应力分析研究进展

评述了波纹管应力理论研究方法的进展情况，围绕解析法、工程近似法和数值法，对波纹管理论研究中的一些主要成果作了较详细的回顾和总结，对各种研究方法作出了评价，展望了亟待解决的一些问题。     

Direct analysis of the perceived importance of attributes of reliability of travel modes in urban travel

Reliability of travel modes was found to be the most important characteristic of transportation systems in several attitudinal investigations of individual travel behavior. This paper represents the first part of a research effort aimed at gaining a better understanding of the characteristics of reliability of transportation modes in urban travel. In this research, reliability characteristics are identified; their importance relative to each other is assessed, and an insight into possible structure of an objective reliability index is discussed. The research is based on perceived values of reliability, which were identified through a large attitudinal survey conducted in the Chicago metropolitan area.