The association between transit access and auto ownership: evidence from Guangzhou,China

In many developing countries, massive investment in transit infrastructure is concurrent with the proliferation of automobiles. Planners expect that investment can slow the growth of auto ownership. However, few studies have examined the relationships between transit access and auto ownership in developing countries, whereas research in developed countries offers mixed findings and the outcomes may not be applicable to developing countries. This study employs a random effect ordered probit model on data collected from Guangzhou residents in 2011–2012. We find that transit access is negatively associated with auto ownership, after controlling for demographics and other built environment variables. This result suggests that, although income is the dominant driver for auto ownership in growing developing countries, transit investment is a promising strategy to slow the growth of auto ownership. This study also highlights the importance of addressing spatial dependency in clustered data.     

Severity of pedestrian injuries due to traffic crashes at signalized intersections in Hong Kong: a Bayesian spatial logit model

The present study intended to (1) investigate the injury risk of pedestrian casualties involved in traffic crashes at signalized intersections in Hong Kong; (2) determine the effect of pedestrian volumes on the severity levels of pedestrian injuries; and (3) explore the role of spatial correlation in econometric crash‐severity models. The data from 1889 pedestrian‐related crashes at 318 signalized intersections between 2008 and 2012 were elaborately collected from the Traffic Accident Database System maintained by the Hong Kong Transport Department. To account for the cross‐intersection heterogeneity, a Bayesian hierarchical logit model with uncorrelated and spatially correlated random effects was developed. An intrinsic conditional autoregressive prior was specified for the spatial correlation term. Results revealed that (1) signalized intersections with greater pedestrian volumes generally exhibited a lower injury risk; (2) ignoring the spatial correlation potentially results in reduced model goodness‐of‐fit, an underestimation of variability and standard error of parameter estimates, as well as inconsistent, biased, and erroneous inference; (3) special attention should be paid to the following factors, which led to a significantly higher probability of pedestrians being killed or sustaining severe injury: pedestrian age greater than 65 years, casualties with head injuries, crashes that occurred on footpaths that were not obstructed/overcrowded, heedless or inattentive crossing, crashes on the two‐way carriageway, and those that occurred near tram or light‐rail transit stops. Copyright © 2017 John Wiley & Sons, Ltd.     

高速公路清障救援资源需求预测综述

清障救援资源是高速公路缓拥堵保畅通的重要保障,对维护路网运营安全具有重要意义.本文在梳理了国内外道路清障救援资源需求分析方法的基础上,分析了目前研究所取得成果与不足,并提出了相应的研究展望.     

道路运输安全管理研究

做好道路运输安全管理工作,既是推动道路运输行业科学发展、健康发展的客观要求和必然选择,也是道路运输行业管理的难点和焦点.通过道路行车事故案例统计分析,文中归纳了我国道路运输行车事故规律特征,并梳理了分析当前道路运输安全管理存在的突出问题.在道路运输安全管理工作基础上,提出了未来我国道路运输安全管理思路.     

进气充量特征参数对 CPF 再生过程的影响

利用AVL BOOST ,FIRE软件分别构建了D19高压共轨柴油机的一维仿真模型和催化型颗粒捕集器（CPF）三维模型,研究了不同进气特征参数对CPF再生过程的影响规律。计算结果表明：随大气氧浓度减小,CPF沉积颗粒的氧化速率和压降的下降速率都显著减缓,其进、出口两端的NOx 及 NO2排放降低;海拔升高不利于CPF的再生,但CPF压降和再生最高温度较低,且能有效减少CPF出口端的NO2排放;海拔对CPF再生过程的影响是大气氧浓度与大气压力的综合效应,其中大气氧浓度占主导作用;针对海拔2 km高原环境,EGR率增大至15％时,CPF再生性能已明显减弱,高原环境下采用EGR进一步加剧CPF的再生困难;EGR率对NO2的降低作用大于其对NO的降低作用。     

太阳能游览船能量平衡及续航里程研究

以某太阳能游览船为对象,分析船机桨能量平衡关系,建立船舶运动能量计算模型,计算匀速航速下的能量消耗,根据电池输出能量与船舶航行消耗能量相等原则,预测游览船续驶里程。通过实际运行数据表明,该模型能够较为准确的计算消耗功率,有效地预测游船的续驶里程。     

混合动力车辆动力耦合装置特性研究

动力耦合装置是混合动力车辆的关键技术之一.文章以行星齿轮式动力耦合装置为研究对象,通过建立模型,从整车角度出发进行了系统仿真研究.结果表明,该动力耦合装置具有良好的综合性能,与同类型的传统燃油车辆相比,可以很好地降低燃油消耗.     

黄海BOB系列客车轮罩总成的改进

BOB系列客车是黄海公司为满足2008年北京奥运会需求精心设计的中高档城市客车。本文以黄海DD6129S06低地板城市客车为例,详细叙述其轮罩结构的改进。     

交通瓶颈下相序设置对路口交通状况影响分析

针对路段发生交通瓶颈时上游路段可能出现的溢流现象,在分析不同相序设置下进入交通瓶颈路段车流构成的基础上,应用车流波动理论,从进入交通瓶颈路段的车流与交通瓶颈通行能力间关系出发,分别就不同相序相同车流量以及相同相序不同车流量时交通瓶颈上游车流的集散波进行分析对比,将周期内不同的相序设置及车流量对交通瓶颈上游溢流情况的影响进行了研究,针对各种情况,得到通过改变相序避免溢流情况发生需要满足的条件。研究结果表明,在某些条件下,相序的变化对避免溢流现象发生的影响不大,而当满足一定条件时,通过改变相序设置可以有效的避免溢流情况的发生。     

基于Wilson熵分布假设的交通公平性量化评价模型

在对交通公平性的量化评价方法进行考察的基础上,从效益分配符合"W ilson熵分布"的假设出发,尝试建立了群体决策型的公平性量化评价模型,该模型综合考虑了区域公平性和不同群体效益归属公平性.对于模型的分析表明交通设施的群体决策型公平性量化评价模型具有最佳解.同时通过数学方法可以证明建立的基于"W ilson熵分布"假设的交通公平性量化评价模型能很好地体现对于弱势群体和不发达区域的效益"补偿"作用.分析结果表明该模型用于交通公平性评价是合理、可行的.