Impact assessment of extreme weather events on transport networks: A data-driven approach

The present paper presents a data-driven method for assessing the resilience of the European passenger transport network during extreme weather events. The method aims to fill in the gap of current research efforts regarding the quantification of impacts attributed to climate change and the identification of substitutability opportunities between transport modes in case of extreme weather events (EWE). The proposed method consists of three steps concerning the probability estimation of an EWE occurring within a transportation network, the assessment of its impacts and the passengers’ flow shift between various transport modes. A mathematical formulation for the proposed data-driven method is provided and applied in an indicative European small-scale network, in order to assess the impacts of EWE on modal choice. Results are expressed in passenger differentiated flows and the paper concludes with future research steps and directions.     

基于客流需求的城市轨道交通动态时刻表优化模型

为使城市轨道交通列车运行时刻表更贴合客流需求,依据不断变化的客流需求确定每列车的发车时刻和停站时间,采用多目标优化方法构建以乘客出行时间费用和列车运行时间费用最小为目标、列车发车时刻和停站时间为决策变量的城市轨道交通动态时刻表优化模型,并采用粒子群算法求解。以广州地铁13号线为例进行验证,结果表明优化后的时刻表更满足客流需求,能有效地提高乘客出行效率,具有更好的动态适应性。     

向量法在不规则隧道边仰坡面积计算中的应用

根据隧道边仰坡三维坐标测量数据,通过计算边仰坡斜面和投影水平面的法向量,进而计算两面之间夹角的方法,反算边仰坡斜面面积,在类似不规则隧道边仰坡等斜面面积计算中具有广泛的应用价值。     

Optimal joint distance and time toll for cordon-based congestion pricing

This paper addresses the optimal toll design problem for the cordon-based congestion pricing scheme, where both a time-toll and a nonlinear distance-toll (i.e., joint distance and time toll) are levied for each network user’s trip in a pricing cordon. The users’ route choice behaviour is assumed to follow the Logit-based stochastic user equilibrium (SUE). We first propose a link-based convex programming model for the Logit-based SUE problem with a joint distance and time toll pattern. A mathematical program with equilibrium constraints (MPEC) is developed to formulate the optimal joint distance and time toll design problem. The developed MPEC model is equivalently transformed into a semi-infinite programming (SIP) model. A global optimization method named Incremental Constraint Method (ICM) is designed for solving the SIP model. Finally, two numerical examples are used to assess the proposed methodology.     

The Kalker book of tables for non-Hertzian contact of wheel and rail

A new regularisation of non-elliptical contact patches has been introduced, which enables building the look-up table called by us the Kalker book of tables for non-Hertzian contact (KBTNH), which is a fast creep force generator that can be used by multibody dynamics system simulation programs. The non-elliptical contact patch is regularised by a simple double-elliptical contact region (SDEC). The SDEC region is especially suitable for regularisation of contact patches obtained with approximate non-Hertzian methods for solving the normal contact problem of wheel and rail. The new regularisation is suitable for wheels and rails with any profiles, including worn profiles.

The paper describes the new procedure of regularisation of the non-elliptical contact patch, the structure of the Kalker book of tables, and parameterisation of the independent variables of the tables and creep forces.

A moderate volume Kalker book of tables for SDEC region suitable for simulation of modern running gears has been computed in co-simulation of Matlab and program CONTACT.

To access the creep forces of the Kalker book of tables, the linear interpolation has been applied.

The creep forces obtained from KBTNH have been compared to those obtained by program CONTACT and FASTSIM algorithm. FASTSIM has been applied on both the contact ellipse and the SDEC contact patch. The comparison shows that KBTNH is in good agreement with CONTACT for a wide range of creepage condition and shapes of the contact patch, whereas the use of FASTSIM on the elliptical patch and SDEC may lead to significant deviations from the reference CONTACT solutions.

The computational cost of calling creep forces from KBTNH has been estimated by comparing CPU time of FASTSIM and KBTNH. The KBTNH is 7.8–51 times faster than FASTSIM working on 36–256 discretisation elements, respectively.

In the example of application, the KBTNH has been applied for curving simulations and results compared with those obtained with the creep force generator employing the elliptical regularisation. The results significantly differ, especially in predicted creepages, because the elliptical regularisation neglects generation of the longitudinal creep force by spin creepage.     

Dynamic simulation of train–truck collision at level crossings

Trains crashing onto heavy road vehicles stuck across rail tracks are more likely occurrences at level crossings due to ongoing increase in the registration of heavy vehicles and these long heavy vehicles getting caught in traffic after partly crossing the boom gate; these incidents lead to significant financial losses and societal costs. This paper presents an investigation of the dynamic responses of trains under frontal collision on road trucks obliquely stuck on rail tracks at level crossings. This study builds a nonlinear three-dimensional multi-body dynamic model of a passenger train colliding with an obliquely stuck road truck on a ballasted track. The model is first benchmarked against several train dynamics packages and its predictions of the dynamic response and derailment potential are shown rational. A geometry-based derailment assessment criterion is applied to evaluate the derailment behaviour of the frontal obliquely impacted trains under different conditions. Sensitivities of several key influencing parameters, such as the train impact speed, the truck mass, the friction at truck tyres, the train–truck impact angle, the contact friction at the collision zone, the wheel/rail friction and the train suspension are reported.     

基于宜兴市居民出行特征的客运交通发展对策研究

居民出行调查是城市交通规划、建设和管理的基本依据．本文根据宜兴市2002年居民出行调查的有关数据,对人均出行次数、平均出行时耗、出行方式构成、出行目的和出行时间分布等进行了分析,并在此基础上,结合宜兴市交通现状及城市总体规划,从优先发展公共交通、重视自行车交通、控制摩托丰发展、加强交通管制、强化市场机制、加强企业管理和政府扶持相结合以及颁布公交行业服务标准等方面,提出了宜兴市客运交通发展的几点对策．     

公路客运市场退出影响因素实证分析

通过对广东省公路客运企业和政府主管部门的问卷调查,采用因子分析方法,从影响客运市场退出的相关主体及相关行为中筛选出关键变量．运用非参数检验过程,就各关键变量对退出的影响程度进行比较,最终得出驾驶员和承包经营人的相关行为对公路客运市场退出最具影响的结论,为政府部门进行行业管理和政策制定提供了实证依据．     

TOD交通走廊形成机理分析及经验借鉴——以美国阿灵顿县R-B走廊为例

TOD（Transit-Oriented Dovelopment,公共交通为导向的城市土地开发）交通走廊是以大运量的客运走廊为载体,通过选择若干站点进行TOD模式的开发,突破传统的单个节点开发形式,充分发挥规模效应,形成整合优势．本文以华盛顿特区西南部的阿灵顿县（Arlington County）的Rosslyn-Ballston轴状走廊（下文简称R—B走廊）为例,从宏观、中观和微观三个层次分析其形成机理,总结出TOD交通走廊建设的成功经验．     

城市轨道交通客运服务标准编制研究

城市轨道交通客运服务标准应主要针对乘客的需求而制定,是当前需要优先制定的服务业标准之一。通过对城市轨道交通客运服务及特性进行分析,结合国际相关服务标准以及我国现行的服务标准及标准化模式,提出了“以人为本”、系统性和与国际接轨的标准编制原则。乘客乘车是一个按时间顺序的活动过程,沿乘客乘车时间次序展开服务次序,是标准编制的重要技术方法。确定城市轨道交通客运服务内容是城市轨道交通客运服务标准编制的一项主要任务。在借鉴国外先进服务标准理念的基础上,通过轨道交通客运服务质量和从乘客实际需求出发来规范服务内容。最后,对乘客相应权益的规定做了说明。