五路交叉口交通改善方法及其应用

五路交叉口通常用环岛来组织交通,随着交通量的迅猛增长,现在成了道路上的主要拥堵点,是交通界公认的比较棘手的问题,探讨五路交叉口的改善方案显得尤为必要。结合城市多路交叉口的常见问题,探讨了五路交叉口设计中的五路环形交叉、五路信号控制、五路环岛加信号控制、五路改四路等方法,分析了各方法的优缺点并提出其适用条件。以实际五路交叉口改造为例,对各个方案进行仿真,并对仿真结果进行对比分析,提出了五路环行交叉口的最优解决方案。     

黏层油合理用量试验及其对路面性能影响机理分析

为探讨黏层油合理用量及其对路面性能的影响机理,采用直剪试验、斜剪试验及小梁弯曲试验分别测定了不同黏层油用最的复合圆柱体试件的抗勇强度及复合小梁试件的抗弯拉应变.研究结果表明:(1)在沥青混凝土路面层间喷洒黏层油,可以增强沥青混凝土面层的结构整体性,并且黏层油的喷洒量存在一个最佳值,在此最佳用量下,沥青混凝土面层层间黏结...     

一款1.5L缸内直喷汽油机的燃烧系统设计

基于进气道三维流场测试装置、定容弹喷雾试验台和光学单缸机测试系统组成的缸内直喷汽油机燃烧系统可视化开发平台,开发设计了满足设计要求的高性能进气道,并匹配了缸盖燃烧室和活塞,有助于缸内混合气的形成,提高燃烧速率;综合考虑排放与机油稀释量的基础上,优化设计了喷雾靶点。对所设计的燃烧系统进行了光学单缸机试验和热力学多缸机试验验证。结果表明,进气道和燃烧室组织引导的气流在缸内形成高滚流,对喷雾油束有强烈的弯卷作用,极大促进了均质混合气的形成,并减小喷雾碰壁的风险;喷雾靶点的合理设计有效避免喷雾油束与壁面的碰撞,减少了机油稀释率和起燃工况HC排放;所设计的燃烧系统搭载1.5TGDI发动机实现了80kW/L、最大扭矩250N·m、排放较低的性能指标。     

Accident investigations for active safety at CHALMERS - new demands require new methodologies

In order to develop efficient active safety systems, knowledge about what causes traffic accidents is required. One way to gather such knowledge is through traffic accident investigations. For the needs of active safety, most current accident investigation methodologies do not provide a sufficiently detailed or theoretically anchored analysis. Therefore, new studies need to be carried out using new theoretical frameworks and analysis methods. At CHALMERS, a new methodology called driving reliability and error analysis method has been developed and tried out during recent years. The methodology, as described and exemplified, shows good promise of meeting the needs of active safety accident investigation projects. Results from studies using the methodology also imply consequences for how benefit estimation of new active safety systems should be carried out.     

LNG重型牵引车经济性及动力性研究

文章针对不同动力匹配的LNG重型牵引车,采用CRUISE仿真分析与车辆实际运行数据分析相结合的方法进行经济性及动力性研究,确定了仿真分析方法的可行性,为通过仿真分析进行动力匹配的优化提供了借鉴.     

交通噪声经济损失估算方法研究

噪声污染带来的经济损失是多方面和难以计算的。本文以交通噪声为例,运用环境经济学的观点和方法,介绍了估算交通噪声污染损失的3种常用方法:损害费用法、意愿型调查评估法和防护费用法,并对它们进行了比较研究。     

鄱阳湖生态经济区文化软实力建设刍议

鄱阳湖生态经济区文化软实力建设是提升鄱阳湖生态经济区整体实力和竞争力的必然要求,是指基于已有文化资源,通过采取相应举措,增强其内在的凝聚力、生命力、创新力和外在的感召力、吸引力、影响力。丰富的文化资源是文化软实力建设的基础。鄱阳湖生态经济区文化资源转化为文化软实力还面临内在凝聚力不强、对外传播力不大等诸多困境,提炼核心价值观、加强传播力度、推进资源开发、吸纳优质人才、强化合作交流、构建长效机制是破解困境之策。     

Economic impact of a supply change in mass transit in urban areas: A Canadian example

This paper aims at estimating the economic impact of a supply change in the bus transit service in a Canadian city of medium size. By using a quasi-experiment approach and a difference-in-differences (DID) estimator, it evaluates the impact of the introduction of a rapid bus transit (RBT) in Quebec City (Canada) through a spatio-temporal analysis of house price variations. The hedonic price model shows that the new service generates an increase in house price ranging from 6.9% to 2.9%, for those properties located close to the service corridor where the population is quite dense and where the service was offered initially. Using sales transaction data and municipal assessment records from 1997, the effect on price is translated into an economic impact for the whole region. The paper shows that the improvement in public transit supply generates, for Quebec City, a significant fiscal impact estimated to $6 M and a plus-value for properties owners close to $35 M over 12 years. Finally, the implications of this kind of analysis for urban planning and development are discussed.     

城市交通综合改善项目经济效益分析方法研究

通过分析综合交通改善的特点,抽象分析各子项目的影响范围,提出现有测算方法存在重复计算的问题。然后,分析各子项目经济效益产生机理和测算指标及其特点,得到对各子项目的经济效益测算是针对几种受益主体进行分析的结论,提出对客车、公交车、自行车、行人和管理单位等受益主体进行综合经济效益分析的方法。     

沥青混凝土路面透层抗剪性能研究

通过直接剪切试验测定不同情况下沥青混凝土路面透层的抗剪强度,试验得到透层抗剪强度的主要影响因素,结果表明透层油的种类及透层油洒布量对其抗剪强度的影响最大。