城市轨道交通单渡线合理线间距的探讨

在城市轨道交通工程的正线、辅助线及配线设计时,需要设置单渡线.由于正常线间距很难满足《地铁设计规范》对单渡线插入短钢轨长度的要求,通常采用加宽线间距的方法解决,但恶化了正线标准、加大工程量.对单渡线的插入短钢轨长度不满足《地铁设计规范》要求时,在单渡线结构不作加强和改进,并以确保行车安全为前提的基础上对单渡线线间距作了探讨.     

D型便梁在小半径曲线及小线间距区段的应用与计算

D型便梁在既有线的顶进施工过程中的应用已经相当普遍 ,在小半径曲线及小线间距区段下D型便梁的架设计算对设计与施工也有着其实际的使用价值。就该问题进行展开 ,阐明D型便梁在各种曲线半径下的布置方式。     

A multi-objective analysis of a rural road network problem in the hilly regions of Nepal

This paper considers the rural road network upgrading problem, using a multi-objective optimization model, to support decision-makers in the choice of roads to upgrade in the hilly regions of Nepal. The model considers two objectives: minimization of user operation costs and maximization of population covered. The problem was solved for a real-world rural road network in the Gorkha district of Nepal. For this case, all non-dominated solutions were obtained and the ones providing more interesting trade-offs were analysed. The model was found suitable for the case under study, and possibly, easily extendable to rural areas of other developing countries.     

The transportation systems of Buenos Aires, Chicago and São Paulo: City centers, infrastructure and policy analysis

We compare the passenger transportation systems of Buenos Aires, Chicago and São Paulo. The selected cities represent distinctive combinations of land-use, infrastructure, and evolution of transport policy. Analysis is centered on accessibility to downtown areas, where transportation processes converge in an environment where space is scarce. In two of the three cities institutional arrays that legally establish unified decision making have shown little capacity to launch fare or physical coordination between modes. In two of the three cities the concentration of public transportation supply to historical downtowns has not been an attraction factor, and downtown uses have expanded to less accessible areas. Gentrification in Chicago is also another process showing that land use changes are related to many factors, transportation being only one of them, and not always a necessary one. In all three cases the use of railways, as a set of inherited infrastructures, has seen an increase whose magnitude suggests a link to modal reassignment due to increasing congestion. Scarcity of space in old downtown areas is being counteracted through more intense use, or through the expansion of vertical space for transportation operations.     

城市新区客运交通需求预测方法研究

城市客运交通需求预测是城市道路交通规划的基础。城市新区因缺乏现状交通调查资料、开发建设速度较快及其交通出行特征，传统客运交通需求预测方法已不再适用。在吸取国内城市道路交通规划实践经验的基础上，针对城市新区背景下道路交通规划的特点及传统客运交通需求预测方法的不足，以城市新区人口和土地利用规划为基础，提出一种面向城市新区的客运交通需求预测方法，可为我国城市新区交通预测提供借鉴。     

天津轨道交通复杂网络和 应急选址研究

天津已逐步形成轨道交通网络化运营模式,但各线路间的应急管理相对独立、协同性差,导致应急资源利用效率低,应急响应不及时。建立基于11条天津轨道交通线路的复杂网络模型,对其进行统计特性分析,开展车站站点失效的脆弱性研究。在考虑需保护的脆弱站点的基础上,建立适用于天津轨道交通网络化运营条件下的应急设施中心选址模型,确定应急设施中心共计26个,同时明确其覆盖范围。选址结果可提高未来线网的应急效率,其分析过程适用于其他轨道交通网络。     

Estimation of Probability of Swarming Pedestrians Violation at Signalized Intersections in Developing Cities

We made an on-site investigation about pedestrian violation of traffic violation decision and the impact of the number of pedestrians in colony that the probability of pedestrian violation rose with the waiting time for simulating mixed vehicles and pedestrians and used the on-site investigation data to validate the model.When traffic volume is light,the error between the simulated values and the measured ones is 2.47%.When traffic volume is heavy,the error is 3.38%.     

人口老龄化背景下香港地铁服务满意度分析与改进策略研究

我国的人口老龄化趋势日益凸显,受到政府和社会的高度关注。实施积极应对人口老龄化国家战略,满足老年人多层次、多样化需求成为国家的中心工作之一。地铁是老年人重要的出行方式和移动性保障,本研究基于270名老年人对香港地铁(MTR)服务满意度的问卷调查数据,建立随机森林模型关联整体满意度与属性满意度,并构建“重要性-满意度”指数识别地铁属性适老化改进的优先级。研究发现：老年人对地铁服务基本满意;老年人重点关注的地铁服务属性是候车空间、优先座位和行车稳定性;老年人较少关注的属性是发车频率和准时性;改进优先级最高的地铁服务属性是优先座位、车厢温度和站点可达性。据此,针对性提出地铁适老化改进策略。     

城市配送中心布局政府干预机制研究

物流设施外迁导致配送活动负外部性增加,损害了公众福利. 本文应用演化博弈论对政府运用经济政策干预城市配送中心布局问题进行了研究,建立了政府和配送企业的静态演化博弈模型,并在模型中考虑了消费者绿色偏好,分析了政府和配送企业的相互作用机理. 此外,还建立了动态税收演化博弈模型,探究动态税收机制下博弈系统演化方向. 通过仿真计算,对比了静态和动态干预机制的优劣;并对税收和消费者绿色偏好系数做了灵敏度分析. 研究结果表明,静态机制下演化博弈系统无法达到渐进稳定状态,动态税收机制下系统能够达到渐进稳定状态,而且税收水平和消费者绿色偏好水平对配送企业抉择有显著影响.     

A Bayesian network approach for population synthesis

Agent-based micro-simulation models require a complete list of agents with detailed demographic/socioeconomic information for the purpose of behavior modeling and simulation. This paper introduces a new alternative for population synthesis based on Bayesian networks. A Bayesian network is a graphical representation of a joint probability distribution, encoding probabilistic relationships among a set of variables in an efficient way. Similar to the previously developed probabilistic approach, in this paper, we consider the population synthesis problem to be the inference of a joint probability distribution. In this sense, the Bayesian network model becomes an efficient tool that allows us to compactly represent/reproduce the structure of the population system and preserve privacy and confidentiality in the meanwhile. We demonstrate and assess the performance of this approach in generating synthetic population for Singapore, by using the Household Interview Travel Survey (HITS) data as the known test population. Our results show that the introduced Bayesian network approach is powerful in characterizing the underlying joint distribution, and meanwhile the overfitting of data can be avoided as much as possible.