A scenario planning approach for the flood emergency logistics preparation problem under uncertainty

This paper aims to develop a decision-making tool that can be used by government agencies in planning for flood emergency logistics. In this article, the flood emergency logistics problem with uncertainty is formulated as two stochastic programming models that allow for the determination of a rescue resource distribution system for urban flood disasters. The decision variables include the structure of rescue organizations, locations of rescue resource storehouses, allocations of rescue resources under capacity restrictions, and distributions of rescue resources. By applying the data processing and network analysis functions of the geographic information system, flooding potential maps can estimate the possible locations of rescue demand points and the required amount of rescue equipment. The proposed models are solved using a sample average approximation scheme. Finally, a real example of planning for flood emergency logistics is presented to highlight the significance of the proposed model as well as the efficacy of the proposed solution strategy.     

德国铁路应急救援体系经验借鉴及启示

德国铁路以国家应急救援体系为基础,建立起制度完善、组织协调、分工合理、装备先进的铁路救援体系,为我国铁路应急救援体系建设提供借鉴。通过分析德国应急救援组织及机构、铁路应急救援体系架构、铁路应急响应流程和铁路救援装备的现状,从应急救援顶层设计、快速应急救援响应流程、装备利用效率等方面,提出德国铁路应急救援体系经验。我国应从强化应急救援社会协同能力,优化突发事件应急响应流程,提高铁路救援起重机综合利用效率、提升应急救援装备水平等方面构建铁路应急救援体系。     

大型铁路客运枢纽设施应急能力匹配度研究

借鉴国内外学者在大型铁路客运枢纽的设施应急能力方面的研究成果,从应急能力与需求匹配度、节点设施匹配度、疏散流线匹配度3个方面,对大型铁路客运枢纽设施应急能力的匹配度进行研究,阐述应急能力与需求匹配度、节点设施匹配度和疏散流线匹配度的概念与测度方法。在此基础上,建立优化模型,在满足疏散流线安全时间的要求下,使大型铁路客运枢纽设施整体协调匹配。     

市域铁路列车运行组织探讨

近年来,我国现有的城市轨道交通系统逐渐难以满足城区与市郊之间的出行需求,市域铁路成为城市群轨道交通发展的新方向,但我国尚缺乏成熟的市域铁路不同等级列车运行组织模式。在分析国内外市域铁路运行组织及不同等级列车开行现状基础上,提出市域铁路开行不同等级列车的运输组织优化方案,优化市域铁路列车等级设置原则、开行方案、换乘模式,以北京城市副中心线(良乡—乔庄东)为例,提出副中心线运行组织优化建议,为实现都市圈城市轨道交通一体化,促进中心城市与周边城市协调发展提供支撑。     

城市交通发展对铁路货运站布局影响的研究

城市区域结构和产业布局的调整、城市规划理念的变化,使铁路货运站的位置需重新确定。城市轨道交通形成网络后,市内运输能力大大提高,铁路枢纽所有为城市服务的设备和设施均可移出市区,城市内的货物运输可由城市轨道交通系统利用凌晨时段完成。为此,提出了铁路枢纽内货运站设置的数量、位置,以及城市内货运集散点位置的确定方法。     

Space-time demand cube for spatial-temporal coverage optimization model of shared bicycle system: A study using big bike GPS data

As a sustainable transport mode, bicycle sharing is increasingly popular and the number of bike-sharing services has grown significantly worldwide in recent years. The locational configuration of bike-sharing stations is a basic issue and an accurate assessment of demand for service is a fundamental element in location modeling. However, demand in conventional location-based models is often treated as temporally invariant or originated from spatially fixed population centers. The neglect of the temporal and spatial dynamics in current demand representations may lead to considerable discrepancies between actual and modeled demand, which may in turn lead to solutions that are far from optimal. Bike demand distribution varies in space and time in a highly complex manner due to the complexity of urban travel. To generate better results, this study proposed a space-time demand cube framework to represent and capture the fine-grained spatiotemporal variations in bike demand using a large shared bicycle GPS dataset in the “China Optics Valley” in Wuhan, China. Then, a more spatially and temporally accurate coverage model that maximizes the space-time demand coverage and minimizes the distance between riders and bike stations is built for facilitating bike stations location optimization. The results show that the space-time demand cube framework can finely represent the spatiotemporal dynamics of user demand. Compared with conventional models, the proposed model can better cover the dynamic needs of users and yields ‘better’ configuration in meeting real-world bike riding needs.     

高速铁路应急调度协同处置流程结构化分析方法研究

高速铁路应急调度处置流程的结构化分析,对于提升应急调度处置效率和质量,推动应急调度智能化进程具有重要意义。针对结构化分析需求,提出一种基于铁路规章的应急调度处置流程分解与重构方法,以图形化方式重构应急调度处置流程,并基于随机Petri网理论建立高速铁路应急调度协同处置流程模型,给出多工种协同的SPN模型建立与等价化简、性能分析的方法,通过计算识别处置流程风险控制点和关键环节,选取场景“运行途中司机发现晃车”建模并分析,分析结果符合现场实际情况,表明该结构化分析方法能够从信息传递和处置流程角度提示风险控制点和关键环节,为多工种协同的应急调度指挥工作提供决策参考。     

六安铁路物流基地选址及平面布置方案研究

为将六安市规划打造成为全国陆路型物流节点城市,发挥六安市区位及交通优势,推动地区产业升级、优化城市发展格局。基于六安地区铁路总图规划,结合城市经济、产业布局、交通条件、用地条件等,确定新建铁路物流基地选址。根据选址车站枣树店站的地理位置、铁路条件和功能分区设计,提出平行铁路布置方案与垂直铁路布置方案2个方案。经综合比选,推荐采用作业效率高、工程代价小的平行铁路布置方案,加快实现六安市物流产业网络化、集约化和信息化,促进区域产业升级转型。     

包西高速铁路引入鄂尔多斯地区方案研究

包西高速铁路作为我国"八纵八横"高速铁路通道中重要的纵向通道之一,建成后呼包鄂城市群和关中平原城市群将实现有效连接。鄂尔多斯市为典型的"一城双核"城市,包西高速铁路的引入将对地区客运布局产生较大影响,根据鄂尔多斯地区城市及铁路现状、城市总体规划及交通规划,结合地区客运量及特点,提出地区内包西高速铁路引入方案及车站设置方案,确定合理的引入及客站布点,研究地区内高速铁路客站布局,结合地区客流特点,确定高速铁路车站分工;合理确定引入地区线、站位方案将有助于完善鄂尔多斯铁路枢纽的客运铁路布局,有助于完善鄂尔多斯地区高速铁路网络,提升呼包鄂城市群的辐射效应,促进城市建设和经济发展。     

A multiple dispatch and partial backup hypercube queuing model to analyze emergency medical systems on highways

The hypercube is a spatially distributed queuing model based on Markovian analysis approximations, used to analyze the configuration and operation of server-to-customer emergency systems. In the present study we adapted the model to analyze emergency medical systems (EMS) on highways, which operate within particular dispatching policies. The study takes into consideration that: the emergency calls are of different types; the servers are distinct (e.g., rescue ambulances, medical vehicles); only certain servers in the system can service calls in a given region (partial backup); and, depending on the type of call, one or more identical or distinct servers are immediately dispatched to service such calls (multiple dispatch). We also consider that the arriving calls take place either along the highway or at the home location of a server – in which case the server does not need to travel to the call location. Finally, we analyzed the computational results of applying such an approach to the case study of an EMS operating on Brazilian highways.     

城际铁路与城市轨道交通售检票互联互通模式研究

为更好的满足国家对现代化城市群发展的要求,提高乘客在城市群内铁路和地铁间换乘的便捷程度,应该加快实现城际铁路和城市轨道交通售检票系统之间的互联互通。基于旅客和管理主体对售检票系统联通的便利需求,提出实名制实体/虚拟一卡通、无碍换乘的实名制实体/虚拟一卡通、二维码互换、一码通、一证通、刷脸通6种方式的互联互通便利模式适应性比较分析,采用符合现阶段铁路和城轨售检票模式的互联互通解决方案。     

The success story of Spanish suburban railways: determinants of demand and policy implications

Ridership of suburban railway services in Spain has experienced a 30% increase during the 1990s. This paper carries out the estimation of an aggregate demand function using panel data from eleven urban areas. Among other results, short- and long-run elasticities with respect to both prices and a quality measure are obtained. These results are used to discuss the policy alternatives that RENFE faces in order to increase its revenue in the future.     

高速铁路柔性时刻表编制研究

随着新兴信息技术与交通的不断融合发展,需求响应型交通已成为未来交通发展的新模式,而柔性时刻表编制问题是决定这一新模式能否在高速铁路应用的关键问题之一。基于旅客预约条件下的需求响应型高速铁路柔性时刻表编制问题,提出完全柔性和部分柔性2种编制模式,构建同时考虑列车开行收益和旅客平均偏差时间的双层优化模型,设计模拟退火算法求解,以厦深高速铁路为例进行案例分析。研究结果表明,柔性时刻表编制模型求解得出的时刻表能够较好地匹配旅客预约的出行时间,有效满足旅客预约需求,提高运营收益,对未来需求响应型高速铁路具有一定参考价值。     

城际铁路列车停站方案的遗传算法求解

我国城市群快速发展,城市间人员交流密切频繁,城际铁路成为城际间旅客的重要出行方式。合理的城际铁路列车停站方案可以提高城际铁路的竞争力,提升城际铁路的分担率。分析停站方案相关的运营收益和旅客出行成本,以铁路运营收益最大和旅客出行成本最小为目标函数,以车站服务频率、设备能力、列车停站次数等作为约束条件,建立城际铁路列车停站方案的多目标混合0-1规划模型,运用理想点法和遗传算法求解。算例结果表明,该模型和算法可以优化得到铁路运营收益和旅客出行成本均较优的停站方案。     

大理动车运用所选址方案研究

随着多条铁路引入大理枢纽及周边路网的完善,枢纽内急需增加动车组运用检修存放设施,以满足旅客出行需求及实现大理地区路网通达的需要。在阐述大理枢纽规划和动车组检修工作量的基础上,确定大理动车运用所规模,分析横列式和纵列式2个布置方案,结合动车运用所选址原则提出蛇山方案、苍甸山方案、凤仪方案3个动车运用所选址方案,从运营长度、工程条件、后期发展等方面对3个方案进行综合比选,最终确定经济合理、适应城市规划及铁路科学发展的蛇山方案。动车运用所的建设研究有利于完善大理枢纽功能,提升铁路区域运输能力。     

Spatial and temporal heterogeneity of the impact of high-speed railway on urban economy: Empirical study of Chinese cities

The relationship between high-speed railway (HSR) construction and economic development has become a significant concern in recent decades. This study uses the spatiotemporal panel data of China's HSR construction and economic development from 2008 to 2018 as bases to discuss the spatial–temporal heterogeneity of the relationship between HSR and the urban economy. Firstly, this research measures the accessibility of different dimensions (i.e. location accessibility, potential accessibility and daily accessibility), and assesses the regional disparity of HSR accessibility and urban GDP using the Gini index. Secondly, the direct and indirect effects of HSR on economic development are analyzed from the global perspective by using the spatial Durbin model. Lastly, the geographically and temporally weighted regression model is applied to assess the spatial–temporal heterogeneity of the correlation between HSR and economic development from a local perspective. The conclusions are as follows. (1) The construction of HSR might reduce the regional disparity of daily accessibility, but expand the disparity of potential accessibility and location accessibility. (2) From a global perspective, HSR has a significant positive impact on urban economic development, but this impact was mainly produced by the spillover effect and not the direct effect. Specifically, the smaller the spatial–temporal distance between cities, the higher the level of regional integration and the better the economic development of cities. (3) The HSR impact on urban economic growth has a periodic feature. The stimulation of large-scale railway construction will expand the economic effect of HSR, although network improvement will gradually converge the corresponding impact. (4) From a local perspective, the HSR impact on economic development has significant spatial heterogeneity. Although HSR has a certain inhibitory effect on the economic development of Eastern China, it has a positive impact on the economic growth of the western region.     

Robust hub network design problem

This paper presents a robust formulation for the uncapacitated single and multiple allocation hub location problem where demand is uncertain and its distribution is not fully specified. The proposed robust model is formulated as a mixed integer nonlinear program and then transformed into a mixed integer conic quadratic program. An efficient linear relaxation strategy is proposed which is found to deliver the optimal solutions for all the cases considered in this paper. Numerical experiments suggest location of more number of hubs when accounting for demand uncertainty using robust optimization compared to the deterministic setting.     

A latent class choice based model system for railway optimal pricing and seat allocation

In this paper, discrete choice methods in the form of multinomial logit and latent class models are proposed to explain ticket purchase timing of passenger railway. The choice model and demand functions are incorporated into a revenue optimization problem which jointly considers pricing and seat allocation. The framework provides insightful policy implications in term of fare and capacity distribution derived from actual passenger behavior. It shows that accepting short-haul demand provides greater revenue than long-haul demand using the same capacity. Revenue improvement ranges from 16.24% to 24.96% in multinomial logit models and from 13.82% to 21.39% in latent class models respectively.     

云南铁路货运量增长问题研究

在分析国内外铁路货运需求增长模型的基础上,提出铁路货运需求增长过程的4阶段划分理论,结合云南铁路发展滞后的现状,建立了消除铁路货运能力限制的货运量增长模型。通过对云南铁路货运量和货运需求量的计算,应用MATLAB仿真技术验证了模型的正确性,并对云南铁路货运量和货运需求量进行了预测。     

复杂山区铁路客运站自动选址研究

无备选站址条件下的客运站自动选址是线站协同优化的前提和基础,而不局限于车站选址的代价最小化,同时考虑连接车站间区间线路的代价具有重要意义。构建复杂山区铁路客运站自动选址模型,首先,建立综合地理信息模型,基于线站一体化的设计理念,实现单个车站选址,确定站心位置及站坪方向;其次,以公路线形优化模型的改进算法完成站—站间自动选线设计;最后,将车站选址代价与区间线路代价紧密结合起来,计算综合代价,实现站址方案的优选。以山区铁路为例对该方法进行验证,结果表明,该方法能高效生成山区铁路车站方案集,并辅助设计人员进行方案优化。