城市轨道交通BOT融资模式中的政府职能

阐述建设-运营-移交(BOT)项目成功的重要条件之一在于政府的积极参与和支持.结合我国第一个运用BOT融资模式建设的城市轨道交通的项目--深圳轨道交通4号线,从法律法规和监管角度,对轨道交通BOT实施过程中政府职能进行探讨,提出应该注意的问题和建议.     

基于MapInfo和MapX的导航电子地图实现

介绍基于Mapinfo制作我国某地电子地图的基本步骤和过程,采用在Visual C＋＋中集成MapX的方法对制作的某地电子地图进行二次开发,实现以地图为背景显示飞行参数、飞机计划航线和即时飞行信息等功能,完成导航电子地图的制作。     

乙醇HCCI燃烧特性试验研究

文中对一台双缸四冲程自然吸气直喷柴油机上进行了乙醇的HCCI的试验,试验分析了过量空气系数和进气温度对乙醇均质压燃燃烧特性的影响。研究结果表明:发动机缸压和压力升高率峰值随着进气温度的上升而增加,并且峰值压力也会提前;过量空气系数的增大,缸压和压力升高率减小。与较小的过量空气系数相比,峰值压力的出现明显推迟。过量空气系数对压力升高率的影响较小,但对放热率的影响相当大。     

Application of Chinese Characters in the Design and Construction of the Badaling Great Wall Station of the Beijing-Zhangjiakou High-Speed Railway北大核心CSCD

The new Badaling tunnel is the longest tunnel on the under-construction Beijing-Zhangjiakou highspeedrailway, with the Badaling Great Wall station to be built in the tunnel. This station, which is under the Badaling Great Wall historic site, is the world’s largest underground high-speed railway station with the most complicated structure and the largest overburden and excavation area. It is therefore a representative project for China’s highspeed railway development strategy, supporting infrastructure facilities for the Beijing Horticultural Expo 2019 and the 2022 Winter Olympics in Beijing, and it is important that it be of high quality and completed safely. In the de-sign and construction of the station, the glyphs of the Chinese characters of "中",”国”,”人”and”品”are used, re-spectively, along the station route, in the rescue and evacuation mode, auxiliary adit and partial excavation, which is a way to successfully integrate the art of Chinese characters into tunnel engineering. © 2018, Editorial Office of "Modern Tunnelling Technology". All right reserved.     

制动卡钳导向销断裂影响因素分析

制动卡钳的功能稳定性是整车制动制动性能关键指标之一,故在产品开发过程中需进行零件级、系统级以及整车级别的测试验证,以满足市场环境中的所有工况下的性能要求.本文以产品验证初期出现的制动卡钳导向销断裂为例,对引起卡钳导向销断裂的试验方法、结构强度等因素进行了研究.分析出引起导向销断裂的关键因素,并通过结构的改进.消除了导向...     

JZD-2型机车整车试验动态检测装置

阐述了采用机车定置试验台试验代替正线试运的可行性。重点介绍提高机车定置试验效率的两项新技术。并列式轨道可保证机车快速安全地自行上下试验台。定量轴距调整机构能实现试验台轴距调整一次自动到位。     

航空电子装备的故障预测法

利用ARMA模型对航空电子装备选定的状态预测量进行估计。实际预测结果表明，当预测状态量选取合适时，用ARMA模型进行预测是比较有效的。     

Traffic assignment considering air quality

This paper presents a methodology of assigning traffic in a network with the consideration of air quality. Traffic assignment is formulated as an optimization problem considering travel cost and on-road emissions. It introduces a cell-based approach to model emission concentrations so that either the average or maximum emissions in a network can be considered in the optimization process. The emissions in a cell are modeled taking into consideration the influence of the emission sources from all cells in the network. A case study demonstrates that minimizing travel cost and reducing air pollutants may not be always achieved simultaneously. The traffic assignment procedure can effectively reduce emission concentrations at those locations with the worst air quality conditions, with only a marginal increase in travel time and average emission concentration in the network.     

汽车出口遭遇运输难题

外向型经济飞速发展的中国,不仅是世界第三大汽车市场,而且也将是国际汽车贸易的主要输出国。作为汽车制造业的战略选择,中国汽车出口所遇到的问题,还不仅仅在于汽车产业自身的竞争力,也在于外销过程中的运力短缺。技术并不尖端的汽车滚装船,为啥舱位难求,为啥价高如许?同样是整机出口的机电产品,船舶咋就不能拉汽车兄弟一把?     

一种VRLA蓄电池的电性能试验及失效模式分析

对一种VRLA蓄电池的部分电性能进行了初步探讨.对电池的容量、内阻、密封反应效率、过充电寿命等进行了一系列的试验.试验结束后,将电池进行了解剖.对电池失效原因进行了分析,主要有三条:①正板栅腐蚀严重,活性物质软化脱落;②电池失水;③负极硫酸盐化.