Possible Sustainability of Intermodal Transportation in Africa

The lack of adequate and modern transport infrastructures makes the cost of transport in Africa higher than the rest of the world. Most of the transport infrastructures that exist were constructed during the colonial era which makes inter-regional connectivity difficult. The African Union in collaboration with other organization has committed to bridge the transport gap in Africa but still, face some challenges. This paper discusses the main issues that contribute for the weak nature of transportation in Sub-Saharan Africa with regards to the main transport modes and seeks to establish the possibility of sustainable intermodal transport through the integration of the different transport modes. Some policy reforms and other bilateral agreements such as deregulating the transport markets in West and Central Africa have been suggested to facilitate the development of an effective and efficient transport network in the Sub-Saharan African region.

High-Capacity Transport Associated with Pre- and Post-Haulage in Intermodal Road-Rail Transport

This paper develops a model for analyzing the potential of longer and heavier vehicles (LHVs) related to pre- and post-haulage in the intermodal rail-road transport chain (IRT). The paper considers the combined economic and emission costs among three different transport networks including intermodal rail-road transport with current Swedish regulatory framework for trucks, intermodal rail-road transport with LHVs, and direct-road transport. The objective is to analyse the potential of high-capacity transport associated with pre- and post-haulage for enhancing the competitiveness of intermodal transport from a full-costs perspective. The model developed is applied to a Swedish context and case study. Research findings reveal that the break-even of the IRT compared to the direct road transport could be significantly lowered, which suggests the LHVs contribute to exploring the market of IRT over smaller flows.

Development Process of Intermodal Transport Solutions: The Case of Dedicated Solutions Based on Large Shippers’ Volumes

The objective of this paper is to create a process view of the development of intermodal transport solution from the basic idea to implementation. Special case of dedicated solutions based on large shippers’ volumes is chosen, where the shippers engage in the development process of the new solutions. Research is conducted using a qualitative approach: multiple case studies. Empirical data has been obtained through in-depth semi-structured interviews with relevant respondents involved in the development projects. Shippers’ perspective on the development process is studied. Development process can be described through a generic four-stage process: Initiation, Planning, Implementation, and Further Development. Different actors and different resources are required at the different stages. The complex process of establishing new intermodal solutions has lacked attention in the intermodal research. Understanding and improving the development process of new intermodal solutions is considered to have an important effect on the viability of intermodal transport and can help to understand the barriers that prevent companies from switching to intermodal. Development process of new dedicated intermodal solutions is a gradual process of building up the transport solution in a continuous interaction between shippers and transport service providers. Research has focused on the shipper perspective on inter-modal transport, showing that switching to an intermodal transport is not simply a mode choice issue, but involves a transition process that takes time, demands resources, cooperation/coordination between multiple parties, may require changes in the supply chain beyond the transport link, involves multiple actors, and involves an industry that is itself in a process of change.

Terminal Location Models for Intermodal Transport Network Optimization

Since rail-road transport uses road and rail networks and requires the transshipment infrastructures at the terminals, its competitiveness depends not only on the costs but also on the location of these terminals. This paper focused on providing a methodology for determining the optimal locations for intermodal freight transportation terminals in consolidation network. The goal is to minimize total costs in order to increase the efficiency of the transportation system. This paper also has allowed us to have an overview of the methods and models that exist for solving the problem of intermodal and terminal locating.

Data Envelopment Analysis Model for Assessment of Safety and Security of Intermodal Transportation Facilities

Following September 11, 2001, numerous security policies have been created which have caused a number of unique challenges in planning for transportation networks. Transportation policy and funding to improve the transportation infrastructure has historically been addressed as individual modes not as intermodal transportation. As a consequence of this inopportune allocation, it is now apparent that the transportation modes are disconnected and have unequal levels of security and efficiency. Improved intermodal connectivity has therefore been identified as one of the main challenges to achieve a safer, secure, and productive transportation network. Tools need to be refined for collaboration and consensus building to serve as catalysts for efficient transportation solutions. In this study, a mathematical model using data envelopment analysis (DEA) was developed and investigated to assess the safety and security of intermodal transportation facilities. The model identifies the best and worst performers by assessing several safety and security-related variables. The DEA model can assess the efficiency level of safety and security of intermodal facilities and identify potential solutions for improvement. The DEA methodology presented is general in its framework and can be applied to any network of intermodal transportation systems. Availability of credible data, complemented with DEA methodology will help in management decisions making concrete safety and security decisions for intermodal transportation facilities.

Intermodal Terminal Localisation Using a Linear Programming Approach: The Case Study of Togo and West African Landlocked Countries

In this paper, four potential cities to host an intermodal terminal for containers flowing through the Togolese transport corridor are examined. The transport cost minimization through the corridor is the main objective. Consequently, the transport modes that offer the least cost to the transport supply chain are proposed. To attain this goal the paper aims to identify the optimal location for an intermodal terminal on the Togolese corridor, by using the mathematical linear programming model. For this, three transport scenarios are analyzed, the rail, the road, and the combination of these two transport modes to each of the landlocked countries (LLCs) capital cities of Burkina Faso, Mali and Niger. Data of the average transport cost per mode, the cargo demand of the LLCs, and the distances from origin to destinations are input in the LINGO software. Based on the optimization results, we find that among the preselected terminals, the city of Mango located at 550 km in the northern part of the country is the optimal host location for an intermodal terminal along the Togolese corridor. The results of this study may be helpful to transport policy makers in the quest of rendering better servicing to the landlocked countries.

Hinterland Intermodal Freight Flow Optimization for Ports Competition Evidence of West Africa ECOWAS Region

Major problem considered in this study was the intermodal routing problem of regional freight transportation in West Africa ECOWAS (Economic Community Of West Africa States), which can be defined as the problem of determining the freight flow quantity, the transportation mode in each transit corridor while satisfying the freight demand at each West Africa transit country (Mali, Burkina Faso and Niger). The objective was to minimize in land transportation costs. In order to solve optimally and represent the problem, this research employed a linear programming model. The model was solved using Lingo Mathematic Application. The model results showed that port oriented freight logistics in west Africa ECOWAS region do not flow along optimal path and such incur longer time and higher logistics cost than is geographically necessary.

基于联邦学习和多方安全计算的海铁联运数据安全共享方法研究

我国海铁联运占港口集疏运比例仍然过低,关键原因之一在于铁路对于港口适运货源的动态信息不明、营销组织不力。铁路货运营销部门缺乏在保证港口、铁路、海关三方数据隐私安全的前提下,根据铁路运力动态主动挖掘港口和海关数据中潜在适运货源的技术方法和手段,难以推出适销对路的运输产品和动态营销手段,也难以为海铁联运基础设施的建设提供有效决策依据。构建基于联邦学习和多方安全计算的铁路-港口-海关数据安全共享方法,使用结合同态加密等多方安全计算技术的梯度提升决策树作为模型训练算法,铁路、港口、海关三方地位对等协作,训练出海铁联运潜在货源识别策略;在该策略的正式运行实现过程中,铁路方能够获得路网各流向潜在适运货源的数量级,各方均看不见、带不走其余参与方的任何原始数据。

考虑海铁联运的集装箱码头泊位分配优化

在海铁联运背景下,协同考虑到港船舶及铁路班列特点,优化集装箱码头泊位分配,对于提高港口作业效率至关重要。在满足码头岸线、泊位水深、岸桥等资源约束前提下,综合考虑船舶服务优先级和偏好泊位、铁路集装箱班列到发时间等约束,以船舶在港停留时间和泊位偏移惩罚时间最小为优化目标,建立海铁联运集装箱码头泊位分配优化模型;针对模型特点,设计自适应遗传算法进行求解,选取计划周期48 h内的到港船舶数据进行案例分析,通过MATLAB数值实验,得到符合船舶服务优先级和泊位偏好要求且契合铁路班列开行计划的海铁联运码头泊位分配方案。数值实验结果表明:在海铁联运协同优化条件下,船舶平均等泊时间为2.9 min,最大等泊时间为11.4 min,同时船舶的靠泊位置与偏好泊位之间的距离均不超过100 m,船舶在港的停留时间及偏好泊位差都得到了较好的控制。研究可进一步优化海铁联运集装箱码头泊位分配方案,有利于提高海铁联运集装箱在港转运效率。

我国铁水联运标准化建设现状研究分析及对策建议

铁水联运标准化是助推铁水联运高质量发展的重要技术支撑。为明晰制约铁水联运高质量发展的标准化问题,准确把握铁水联运标准化工作任务,本文在文献调研、实地调研、专家座谈和问卷调研的基础上,全面梳理了我国铁水联运标准化取得的成绩,深入研究了基础设施标准不健全、服务规则不统一、危险货物界定标准不一致、信息交换标准有待完善、标准实施效果不佳等制约铁水联运高质量发展的标准化问题,并从重点标准制修订、标准实施评估、标准宣贯和推广应用等方面提出了对策建议,为加强铁水联运标准化工作提供决策支持。

基于信令数据的城市群空铁联程客流识别及预测框架

针对城市群空铁联程客流需求获取困难、客流规律难以把握的问题,提出一套集成空铁联程客流识别及预测模块的综合分析框架.首先,考虑交通枢纽的空间范围及旅客出行的时空特征,提出一种基于信令数据的空铁联程客流识别方法,并挖掘其时空分布规律.然后,在双向门控循环神经网络模型(Bidirectional Gated Recurrent Unit,BiGRU)的基础上,引入时间周期编码,构建具有时间周期性的双向门控循环神经网络模型(Temporal-Bidirectional Gated Recurrent Unit,T-BiGRU)对空铁联程客流进行预测.最后,以京津冀城市群为实例,对研究框架进行验证.研究结果表明:京津冀城市群空铁联程客流呈现出明显的聚集分布特征,其中北京南站—天津站—天津滨海机场和北京西站—正定机场站—石家庄正定机场两个场景的联程客流占比最高,超过联程客流总量的65%;T-BiGRU模型可以对联程客流的需求进行精准预测,对两个主要场景的双向联程客流的预测精度均超过了89%,优于多个基线模型.研究结果可为城市群空铁协同发展及空铁联程服务优化提供参考.

中转点风险分级收费的危险品多式联运网络设计

近年来,危险品多式联运被广泛应用,而网络中转点由于转运量集聚,导致安全风险较高。为了有效控制危险品多式联运风险,政府可以通过中转点合理选址与分级收费,引导企业合理规划危险品运输路径。首先提出基于中转点风险分级的中转点选址与收费策略,建立危险品多式联运网络设计双层规划模型,上层为网络总风险最小化和总运输成本最小化的中转点选址与分级收费定价问题,下层为各运输事件成本最小化的运输路径规划问题。然后,使用KKT条件转换下层模型为等价约束条件,实现模型单层化,利用Gurobi求解模型。最后,通过算例表明网络风险和运输成本随着中转点数量的增加而降低,证明了中转点分级收费策略可以有效调控危险品多式联运网络风险。

北部湾港平陆运河江海联运方案研究

平陆运河始于西江航运干线中上游的西津枢纽水库支流平塘江口,终于北部湾港,是优化提升全国水运网络、加快建设国家综合立体交通网的联网工程,是建设西部陆海新通道、加快建设交通强国的标志性工程。根据《国家综合立体交通网规划纲要》部署,北部湾港总体规划正在编制,需要统筹考虑平陆运河江海联运枢纽空间布局和平面布置方案。综合考虑平陆运河江海联运量、北部湾港各港区建港条件和资源容量,以及既有港口资源利用情况,按照“就近转运、用足存量”的原则,因地制宜提出分货类的江海联运枢纽布局,制定了大小泊位能力匹配、运输组织高效的平面布置方案,同时也提出明确防城港域航区划分、研究开通防城港水运疏港通道(皇城坳运河)、有序推进现状码头升级改造等建议,为平陆运河建设投产后江海联运平稳运行提供技术支撑。

南京铁路枢纽总图规划深化研究

以《交通强国建设纲要》等上位规划为引领,从国际运输、国内中长途运输、南京都市圈、枢纽客货运输体系建设的角度,提出目前南京铁路枢纽存在的问题。通过分析枢纽近远期客流情况,介绍路网构成,从国际运输、国内运输、过江通道、客运站分工调整等方面提出南京铁路枢纽总图规划优化方案,以期打造国内领先、国际一流的铁路枢纽。通过定量分析可知,枢纽优化后,相关车站、区间线路、过江通道的能力满足远期运输需求,并且对国际国内运输体系建设、都市圈城市发展都具有显著促进作用。

基于生产计划协同的商品车海铁联运班列开行方案优化研究

在物流业制造业深度融合创新发展的背景下,编制列车开行方案的同时考虑与主机厂生产计划的协同配合对推动商品车海铁联运高质量发展有着重要意义。为助力主机厂精益化管理、促进商品车海铁联运降本增效,从优化商品车海铁联运各环节衔接的角度出发,基于主机厂生产计划特点和海铁联运作业流程,综合考虑海运船期、班列开行方案和主机厂生产计划的协同配合,研究商品车海铁联运班列开行方案的优化方法。在构建商品车海铁联运动态运输服务网络的基础上,假设一定决策周期内生产计划和备选船期已知,以最小化海铁联运系统总物流成本为目标,以网络流平衡、弧段能力和班列编组数量要求等为约束条件,建立班列开行方案的优化模型,确定决策周期内班列开行方案和对接船期的选择。选取商品车海铁联运典型案例进行求解验证和灵敏度分析,并与原模式下船期确定和产运分离两个情景进行比较分析。由重庆鱼嘴站—广州港的商品车海铁联运案例分析可知,协同生产计划模式下的目标函数值对比船期确定情景和产运分离情景分别降低了147 400元和80 500元,并在一定程度上改善了运输时效。算例结果表明,在组织商品车海铁联运时将主机厂生产计划纳入考虑能够有效降低物流成本,提高运输效率;所提模型能够为海铁联运班列的开行方案决策提供有效参考。

中铁集装箱公司国内多式联运班列提质升级策略研究

中铁集装箱公司作为国有大型集装箱运输企业,扎实推进集装箱国际、国内货运代理、接取送达、堆存保管等现代物流服务产品,以“公转铁、散改集”作为重要突破口,大力发展铁路集装箱多式联运,全面深度融入我国多式联运体系,整体发展成效显著、增长动力持续显现。通过分析中铁集装箱公司国内多式联运班列发展情况、目前多式联运班列开行存在的问题与短板,提出以加快国内班列运输组织、物流产品、箱型装备、数字平台、内部协同、经营模式等“六个升级”为主线,推动中铁集装箱公司国内多式联运班列实现“质的有效提升”和“量的持续增长”的策略。

我国西部陆海新通道的港口腹地分析

运用多种运输方式下的基础设施地理空间数据和OD流量大数据,识别西部陆海新通道主要港口潜在腹地和真实腹地的空间格局,评价两类腹地的空间匹配关系。结果表明:(1)西部陆海新通道主要港口两类腹地的范围大致相同,腹地内部竞争力的空间分布存在差异;(2)西部陆海新通道主要港口的潜在腹地覆盖范围较广但竞争力不强,通道对于时间价值更高的货物更具吸引潜力;(3)西部陆海新通道主要港口的真实腹地覆盖范围在运输方式间存在显著差异,公路腹地与港口邻近而铁路腹地与港口分离;(4)交通基础设施质量和运输服务水平是影响两类腹地匹配关系的重要因素,大能力运输通道匮乏导致广西和通道西侧的运输供给能力较弱,班列竞争力不足制约了川渝地区的通道运输份额。未来,应提高西部陆海新通道建设的供需匹配针对性,拓展建设中缅印度洋新通道,以进一步保障我国海外战略性关键资源的供应安全。

粤西砂石骨料海铁联运陆港运输组织方案探讨

粤西地区拥有良好的建筑用花岗岩矿产资源禀赋,结合地区交通状况,发挥海铁联运优势,花岗岩砂石骨料通过铁路运至港口装船。采用底开门漏斗车运输砂石骨料,上游矿区建设集装站设环形装车线及散料快速装车系统,开行矿区至港湾站的循环固定车底直达列车,港口建设港湾站设贯通式砂石骨料卸车线,合理匹配底开门漏斗车与卸料槽的适应性。研究集装站装车作业方式和车站布置形式,确定铁路装车作业流程,通过分析港湾站运输组织方案和卸车作业流程,选择一站两场纵列式港湾站布置形式,按照海铁联运产业政策,结合供应链环节中铁路系统、港口系统和海运及装船系统多要素比选得出推荐意见,为采矿业企业的砂石骨料陆港运输提供智能高效、绿色环保的解决方案。

考虑区域风险公平的危险品公铁联运路径优化

为消除危险品运输路径中各区域因承担风险不同所带来的不公平状态,创新提出考虑区域风险公平的危险品公铁联运路径优化方法。该方法选用公铁联运长距离大批量运输的危险品,针对运输路径中各区域风险不公平的现象,采用途中风险补偿与转运风险补偿之和定义的风险补偿成本量化区域风险公平性。在此基础上构建了运输风险最小、风险补偿成本最小、运输费用最小的3目标危险品公铁联运路径优化模型,并设计蚁群算法对多目标路径优化模型进行求解。结果表明,所提出的模型结果对比传统模型在运输风险和运输费用差异不大的情况下,风险补偿成本显著降低,有效提高了区域风险公平性。该路径优化方法能够为决策者提供安全性高、区域风险公平性高且经济性好的路径方案参考。

集装箱海铁联运补贴优化研究

补贴是一种被政府广泛采用且能够有效促进海铁联运发展的措施。本文研究包括3种运输方式和两个起运港的集装箱运输系统中的海铁联运协同补贴优化问题。首先,构建双层规划模型描述政府与托运人之间的博弈关系,上层模型从政府角度出发,以海铁联运运量最大为目标,确定海铁联运班列单个重箱补贴金额;下层模型基于熵最大化理论,构建能力约束型巢式Logit模型描述托运人对起运港和运输方式的选择行为。其次,通过Karush-Kuhn-Tucker条件将双层模型转化为单层模型,并利用松弛迭代算法求解。结果表明:补贴会促进海铁联运运量的增长,其增量主要来自公海联运转移的货运量,少部分来自水水联运转移;相比于不协同补贴,协同补贴不仅显著降低单箱补贴金额,还能提高海铁联运运量;货物时间价值对补贴效果产生影响,补贴具有中等时间价值货物的托运人将会获得最佳结果。