运行速度研究成果在张承高速公路中的应用

根据运行速度在张承高速公路中的应用和对运行速度预测结果的分析,找出所存在的问题和不足,可为进一步的研究工作指明方向。     

三峡库区水上安全虚拟仿真系统探究

通过对三峡库区水上安全形势的分析,探讨了虚拟仿真在三峡库区水上安全管理中的应用,提出了三峡库区水上安全虚拟仿真系统的设计思路,给出了三峡库区水上安全虚拟仿真系统的总体构架。     

山区高速公路线形安全协调度评价

从驾乘人员的角度出发,深入分析山区高速公路线形安全系统各组成要素,选取影响公路线形与安全协调度的指标,并引入群层次分析法建立山区高速公路线形安全协调度评价综合指标体系,且通过统计高速公路设计专家的咨询结果来确定评价指标权重。实例分析表明该方法是可行的,为山区高速公路线形设计进行有效的安全性评价奠定了基础,具有较好的现实意义和应用价值。     

某中体驾驶室的车身总布置设计

本文介绍了某重卡中体驾驶室车身总布置设计,首先对驾驶员A柱双目障碍角及左右后视镜视野进行校核,然后设计相应的雨刮器,并对所设计的雨刮进行运动分析、刮刷面积进行校核,校核结果均满足标准要求;最后以车身总布置图的形式将车身总布置设计及校核的其他关键参数体现出来。     

阴阳离子穿插的配位聚合物：｛［MoS4Cu4（4，4′-bpy）4］［MoS4Cu4（4，4′-bpy）2I4＆#183;4H2O］｝n的合成和晶体结构

通过一种有效的构建三维M/S/Cu配位聚合物的方法,成功合成了一个新的基于鞍状单体[ MoS4 Cu4]的阴阳离子穿插的三维配位聚合物｛[MoS4Cu4（4,4′-bpy）4][MoS4Cu4（4,4′-bpy）2I4＆#183;4H2O]｝n．X射线单晶衍射表明,该晶体属于四方晶系,空间群为I41/acd,a＝24.830（3）？,b＝24.830（3）？,c＝28.208（6）？,α＝β＝γ＝90＆#176;．晶体结构分析显示,配位聚合物1由穿插的阳离子[MoS4Cu4（4,4′-bpy）4]2＋和阴离子[MoS4Cu4（4,4′-bpy）2I4＆#183;4H2O]2-组成的三维钻石状配位聚合物．     

基于交通仿真的区域交通协同优化控制系统

提出采用基于交通仿真的区域交通协同优化控制系统,实现区域交通运行态势的评价、公交需求管理和区域动态诱导。阐述区域交通协同优化控制系统的体系框架和层次结构,并详细讨论交通仿真在区域交通协同控制中的应用方法。该系统的建设对于提升区域交通运行效能,缓解交通拥堵,提高道路交通安全具有重要意义。     

基于PFC的桩承式路堤土拱效应机理研究

应用PFC3D软件,模拟桩承式路堤土拱效应,分析土体颗粒体系中力链的分布情况及土体孔隙比、配位数与土拱效应的关系。研究结果表明:桩土相对位移出现时,路堤土体中力链明显偏转,并发展成一拱形;土体成拱过程中,孔隙比会发生突变;桩土相对位移对路堤土体的影响存在渐进性;配位数在路堤土体中的分布,呈现中部高于上、下部的趋势,证明土拱拱体的形成;在较小或较大相对位移情况下,土体内部颗粒运动比较活跃,土拱效应发挥明显。     

Policy Simulation for New BRT and Area Pricing Alternatives Using an Opinion Survey in Jakarta

Abstract

An area pricing scheme for Jakarta, Indonesia, is currently under review as a transportation control measure along with the operation of new bus rapid transit (BRT) system. While this scheme may be effective for congestion reduction in the central business district (CBD), provision of alternative means of transportation for auto users that are ‘pushed-out’ is of great importance to obtain public acceptance. Hence, it is necessary to simulate simultaneously the area pricing scheme and the BRT development which may serve as an alternative for assumed ‘pushed-out’ auto users. Utilizing data from an opinion survey, this paper studies how BRT and auto ridership are likely to vary as a function of traveler and system attributes. Additionally, the study attempts to evaluate the way this new travel mode is distinguished from other existing conventional transportation alternatives in Jakarta. The survey data contains socioeconomic information of over 1000 respondents as well as details of to-work/school trips to the CBD including mode, travel cost, time, etc. Respondents were asked about their willingness to shift from their current mode to BRT to make the same travel for different BRT fare levels. Modeling efforts suggest that a mixed logit model performs better in explaining choice behavior. Therefore, this model was used for policy simulation. The simulation results brought about many implications as to the tested policies. While the developed models may be applied only to future BRT corridors in which the survey was conducted, they capture the key variables that are significant in explaining mode choice behavior and present great potential for practical use in policy simulation and analysis in a large metropolitan area of the developing world.     

Slot misuse phenomena in capacity-constrained airports with seasonal demand: the Greek experience

Abstract

Airport slot misuse disturbs the efficient and continuous operation of capacity-constrained airports, leading to congestion and delay problems. Deviations from the coordinated schedule in regional airport systems that feature seasonal demand and delays in certain peak periods are studied in this article. The Greek airport system is considered as a case study. Deviations are quantified by computing the difference between scheduled and actual aircraft arrival times as well as the hourly slot capacity utilization ratio. Two collective indicators for airport benchmarking are proposed. An in-depth analysis of slot allocation deviations and the delays they cause is carried out for a representative sample of airports that are classified according to the proposed indicators. A brief discussion on potential measures to mitigate slot misuse is also presented.     

现代导轨电车与两江新区适应性研究

现代宁轨电车作为一种现代化的公共交通工具,与城市地铁、轻轨、快速公交等共同构成城市快速公共交通系统。在我国,天津滨海新区、上海浦东新区相继建成了现代导轨电车公共交通系统。在分析了现代导轨电车的特点并总结国内现代导轨电车应用与实践的基础上,结合两江新区特点,探讨了现代导轨电车与两江新区发展的适应性与发展模式。认为现代导轨电车与两江新区的有机结合对建设“畅通出行”“环境友好”的两江新区公共交通,缓解城市交通压力,丰富重庆公共交通形式,提升城市形象具有重要的意义。