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A reinforcement learning approach to solving very-short term train rescheduling problem for a single-track rail corridor 解决单轨铁路走廊极短期列车重新调度问题的强化学习方法
IF 2.6 Q3 TRANSPORTATION Pub Date : 2024-09-25 DOI: 10.1016/j.jrtpm.2024.100483
Jin Liu, Zhiyuan Lin, Ronghui Liu
Railway operations are regularly affected by incidents such as disturbances and disruptions, which cause temporary operational restrictions to the trains in the network. Compared to real-time disturbances and disruptions, sometimes these incidents can be known at a short notice, e.g., 24–48 h beforehand, which is known as the Very-Short-Term-Planning in British rail operations. This paper presents a novel reinforcement learning based approach for rescheduling train services for in a single-track corridor with bi-directional traffic. As an important subfield of machine learning, reinforcement learning offers an alternate strategy for tackling the NP-hard train (re)scheduling problems and shows its advantages in balancing computational efficiency and solution quality. We propose a Q-learning approach with a tiered rewarding strategy and lightweight train representation in state vectors, which enables more efficient learning and knowledge sharing among homogeneous trains. Compared with an existing reinforcement learning approach, our proposed method can find better quality solutions due to its unique representation of state vectors and a novel tiered rewarding/punishing mechanism, overcoming certain disadvantages in existing approaches. Knowledge reusability is another advantage of the proposed approach, as prior knowledge obtained from training one instance can significantly enhance the performance of another, potentially more challenging, instance on the same corridor with substantially reduced computational time and effort on algorithm development. We also discuss the potential applications of the knowledge reusability feature inherent in reinforcement learning algorithms, which we believe will benefit the entire industry in addressing NP-hard problems through data-driven technologies.
铁路运营经常会受到干扰和中断等事故的影响,这些事故会对铁路网中的列车造成临时运营限制。与实时干扰和中断相比,这些事故有时可以在很短时间内(如 24-48 小时前)被知晓,这在英国铁路运营中被称为 "短期规划"(Very-Short-Term-Planning)。本文提出了一种基于强化学习的新方法,用于在双向交通的单轨走廊中重新安排列车服务。作为机器学习的一个重要子领域,强化学习为解决 NP 难度的列车(重新)调度问题提供了另一种策略,并显示了其在平衡计算效率和解决方案质量方面的优势。我们提出了一种 Q-learning 方法,该方法采用分层奖励策略和轻量级的状态向量列车表示法,能在同质列车之间实现更高效的学习和知识共享。与现有的强化学习方法相比,我们提出的方法因其独特的状态向量表示法和新颖的分层奖励/惩罚机制,可以找到更高质量的解决方案,克服了现有方法的某些缺点。知识的可重用性是所提方法的另一个优势,因为从一个实例的训练中获得的先验知识可以显著提高同一走廊上另一个可能更具挑战性的实例的性能,同时大幅减少算法开发的计算时间和工作量。我们还讨论了强化学习算法固有的知识可重用性特点的潜在应用,相信这将有利于整个行业通过数据驱动技术解决 NP 难问题。
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引用次数: 0
Shippers/freight forwarders’ acceptance of dedicated rail freight corridors for freight mobility in India 托运人/货运代理对印度货运专用铁路走廊的接受程度
IF 2.6 Q3 TRANSPORTATION Pub Date : 2024-09-14 DOI: 10.1016/j.jrtpm.2024.100481
Sowjanya Dhulipala , Gopal R. Patil

This paper investigates the acceptance of a mega rail freight infrastructure as a sustainable alternative to road transport for domestic freight movements in India. The dedicated rail freight corridors (DFCs) are the freight-only rail corridors proposed by the Indian government to improve freight mobility from a sustainable outlook. A shipper/freight forwarder survey was conducted to gather information on mode attributes and their stated preferences toward DFCs. We employ discrete choice (binary logit) and machine learning algorithms (random forest and extreme gradient boosting) to analyse the choice behaviour. The machine learning methods exhibited higher prediction accuracy, while discrete choice models offered better interpretability. On-time performance and transport costs are crucial factors that influence mode choice. Large-scale companies are more willing to shift to DFCs compared to small and medium firms. The policy scenario analysis indicates that providing a better on-time performance can gain a substantial share of DFCs.

本文研究了在印度国内货运中将超大型铁路货运基础设施作为公路运输可持续替代方案的接受程度。专用铁路货运走廊(DFC)是印度政府提出的货运专用铁路走廊,旨在从可持续发展的角度改善货运流动性。我们对托运人/货运代理进行了调查,以收集有关模式属性及其对 DFCs 偏好的信息。我们采用离散选择(二元 logit)和机器学习算法(随机森林和极端梯度提升)来分析选择行为。机器学习方法的预测准确率更高,而离散选择模型的可解释性更好。准时率和运输成本是影响模式选择的关键因素。与中小型企业相比,大型企业更愿意转向 DFC。政策情景分析表明,提供更好的准点率可以获得大量的双向燃料电池份额。
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引用次数: 0
Exploring the relationship between the determinants and the ridership decrease of urban rail transit station during the COVID-19 pandemic incorporating spatial heterogeneity 结合空间异质性,探讨 COVID-19 大流行期间城市轨道交通车站乘客量减少的决定因素与乘客量减少之间的关系
IF 2.6 Q3 TRANSPORTATION Pub Date : 2024-09-14 DOI: 10.1016/j.jrtpm.2024.100482
Junfang Li , Haixiao Pan , Weiwei Liu , Yingxue Chen

The study explores the relationship between the determinants and the ridership decrease incorporating spatial heterogeneity. ARIMA model is utilized to estimate the normal ridership assumed absence of COVID-19. Geography weighted regression (GWR) with Gaussian kernel function is constructed for regression. The K-means algorithm is applied to cluster the stations based on coefficients. Stations of Tokyo case are clustered into 2 groups: city area and western ward which represents mainly suburban areas. City stations are mainly influenced by the number of transfer lines, distance to the CBD, number of jobs and residents. In the western ward, the level of importance that residents place on public health primarily influences the ridership decrease. The implementation of work-from-home policies makes number of jobs a positive impactor on the decrease in ridership, with a greater impact observed on urban stations compared to suburban stations. City residents tend to engage in more travel than suburban residents because of less spacious living environments, which partially offsets the decrease in ridership. The findings offer parameters for predicting ridership of both city and suburban stations during public health emergency events, such as COVID-19. They can assist URT operators in developing strategies for balancing passenger demand and operational costs.

本研究探讨了决定因素与乘客量减少之间的关系,并纳入了空间异质性。利用 ARIMA 模型来估计假定不存在 COVID-19 的正常乘客量。利用高斯核函数构建地理加权回归(GWR)进行回归。应用 K-means 算法根据系数对车站进行聚类。东京案例中的站点分为两组:城区和主要代表郊区的西区。市区车站主要受换乘线路数量、与中央商务区的距离、工作岗位和居民数量的影响。在西区,居民对公共卫生的重视程度主要影响乘客量的下降。居家办公政策的实施使工作岗位数量成为乘客量减少的一个积极影响因素,与郊区车站相比,市区车站受到的影响更大。由于居住环境不宽敞,城市居民往往比郊区居民出行更多,这部分抵消了乘客减少的影响。研究结果为预测 COVID-19 等公共卫生突发事件期间城市和郊区车站的乘客人数提供了参数。它们可以帮助城市轨道交通运营商制定平衡乘客需求和运营成本的策略。
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引用次数: 0
Industry 4.0 for passenger railway companies: A maturity model proposal for technology management 铁路客运公司的工业 4.0:技术管理成熟度模型建议
IF 2.6 Q3 TRANSPORTATION Pub Date : 2024-09-11 DOI: 10.1016/j.jrtpm.2024.100480
Michael Luciano Chaves Franz , Néstor Fabián Ayala , Ana Margarita Larranaga

The railway sector is a relevant segment for the transportation of people and goods, and its efficiency and sustainability are crucial for fostering economic development and minimizing environmental impact. This research proposes an Industry 4.0 maturity model for passenger railway companies to manage emerging technologies, aiming to enhance them holistically to leverage the internal and external business dimensions. An exploratory and qualitative approach was employed, involving semi-structured interviews with experts in Brazilian railway transport. Based on the opportunities and Key Performance Indicators identified within the sector, we developed an Industry 4.0 maturity model for companies and subsequently tested it in collaboration with a transport operator. The findings suggest that the proposed Industry 4.0 maturity model can effectively guide practitioners in applying advanced technologies for robust and efficient train operations, prescriptive maintenance, strong supply chain management, and improved passenger experience and worker performance. This research provides a noteworthy and substantial contribution by introducing unprecedented frameworks that offer a holistic view of Industry 4.0 in the context of passenger railways. The study's practical impact is aiding passenger railway companies to navigate their Industry 4.0 journey. Academically, the research contributes to advancing the holistic understanding of Industry 4.0 as an ongoing phenomenon, enriching the academic discourse by discussing published works and presenting empirical data from railway companies.

铁路部门是人员和货物运输的相关部门,其效率和可持续性对于促进经济发展和最大限度地减少对环境的影响至关重要。本研究为铁路客运公司管理新兴技术提出了一个工业 4.0 成熟度模型,旨在全面提升这些技术,充分利用内部和外部业务维度。研究采用了一种探索性的定性方法,对巴西铁路运输领域的专家进行了半结构化访谈。根据在该行业内发现的机遇和关键绩效指标,我们为企业开发了一个工业 4.0 成熟度模型,随后与一家运输运营商合作对其进行了测试。研究结果表明,所提出的工业 4.0 成熟度模型可以有效地指导从业人员应用先进技术,以实现稳健高效的列车运行、规范性维护、强大的供应链管理,并改善乘客体验和员工绩效。这项研究引入了前所未有的框架,在客运铁路的背景下提供了工业 4.0 的整体视角,从而做出了值得注意的实质性贡献。这项研究的实际影响是帮助铁路客运公司踏上工业 4.0 的征程。在学术方面,该研究有助于推动对工业 4.0 这一持续存在的现象的全面理解,通过讨论已发表的作品和展示铁路公司的经验数据,丰富学术话语。
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引用次数: 0
Freight train scheduling for industrial lines with multiple railway undertakings 多条铁路工业线路的货运列车调度
IF 2.6 Q3 TRANSPORTATION Pub Date : 2024-08-21 DOI: 10.1016/j.jrtpm.2024.100466
Daniel Haalboom, Nikola Bešinović

With the liberalisation of the rail freight market, the number of railway undertakings in operation is increasing. Trains run by several railway undertakings (RUs) converge at industrial lines leading up to terminals. Here, uncoordinated interaction between mainline RUs and limited infrastructure capacity leads to bottlenecks, which reduces resource utilisation of railway undertakings. Outsourcing last-mile operations to an independent local railway undertaking can improve capacity utilisation and decrease the time engines of mainline engines spend within the considered network. In this paper, we propose the Industrial Line Scheduling Problem with multiple RU, a resource scheduling model for freight trains at industrial lines. The aim is to minimise unproductive time of mainline engines and the number of deployed local engines. The results show that the potential savings per employed local engine are highly dependent the timetables of inbound and outbound trains within the network, the dwell time of railcars and on the degree of local railway undertaking involvement.

随着铁路货运市场的开放,运营中的铁路企业数量不断增加。多家铁路公司(RUs)运营的列车在通往终点站的工业线上汇集。在这里,干线铁路公司之间不协调的互动和有限的基础设施能力导致瓶颈,从而降低了铁路公司的资源利用率。将 "最后一英里 "的运营外包给独立的地方铁路企业,可以提高运力利用率,减少干线发动机在所考虑的网络中花费的时间。在本文中,我们提出了具有多个 RU 的工业线路调度问题,这是一种工业线路货运列车的资源调度模型。其目的是最大限度地减少干线发动机的非生产时间和部署的本地发动机数量。结果表明,每台本地发动机的潜在节余与网络内进出港列车的时刻表、轨道车的停留时间以及本地铁路企业的参与程度密切相关。
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引用次数: 0
Trajectory optimization for heavy-haul trains considering cyclic braking under complex operating conditions 复杂运行条件下考虑循环制动的重载列车轨迹优化
IF 2.6 Q3 TRANSPORTATION Pub Date : 2024-07-25 DOI: 10.1016/j.jrtpm.2024.100462
Min Zhou , Yuesong Liu , Hongwei Wang , Hairong Dong

Heavy-haul railways (HHRs) pose significant challenges due to their substantial traction weight, extended train length, and complex operational environments. Heavy-haul trains (HHTs), equipped with traditional pneumatic control braking systems, must adopt cycle braking strategies on long downhill slopes. The varying traction masses of HHTs on these railways lead to diverse maneuvering characteristics, presenting challenges for drivers and dispatchers in unforeseen circumstances. To enhance transportation efficiency and mitigate operational complexities, a trajectory optimization method is formulated for determining the optimal trajectory of HHTs with different traction masses under complex conditions, including long downhill slopes, temporary speed limit sections, and regular sections. It considers the dynamics of train traction, braking, and coasting at each phase, optimizing objectives such as train operation efficiency, energy consumption, and pneumatic braking times. A linear weight search algorithm ensures punctuality, and the model is linearized into a mixed-integer linear programming (MILP) form using segmented and stepwise functions to align with operational realities. Simulation experiments utilizing real data and various HHT configurations validate the efficacy of the proposed approach against alternative methods. This method offers precise trajectory optimization under complex conditions, providing valuable guidance for dispatchers and drivers in the heavy-haul railway sector.

重载铁路(HHR)因其牵引重量大、列车长度长和运行环境复杂而面临巨大挑战。配备传统气动控制制动系统的重载列车(HHT)必须在长下坡时采用循环制动策略。在这些铁路上,重载列车的牵引质量各不相同,导致操纵特性也各不相同,在不可预见的情况下给驾驶员和调度员带来了挑战。为了提高运输效率并降低运营复杂性,本文提出了一种轨迹优化方法,用于确定不同牵引质量的高速列车在长下坡、临时限速路段和常规路段等复杂条件下的最优轨迹。它考虑了列车在每个阶段的牵引、制动和滑行动态,优化了列车运行效率、能耗和气动制动时间等目标。线性权重搜索算法可确保正点率,模型线性化为混合整数线性规划(MILP)形式,使用分段函数和逐步函数,以符合运行实际情况。利用真实数据和各种 HHT 配置进行的模拟实验验证了所提方法与其他方法相比的有效性。该方法可在复杂条件下提供精确的轨迹优化,为铁路重载运输部门的调度员和司机提供有价值的指导。
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引用次数: 0
Comprehensive examination of regional railway passenger behavior and dwell time components: Insights from video-based observations in Victoria, Australia 全面考察地区铁路乘客行为和停留时间构成:澳大利亚维多利亚州视频观察的启示
IF 2.6 Q3 TRANSPORTATION Pub Date : 2024-07-11 DOI: 10.1016/j.jrtpm.2024.100464
Kenneth Ng, Nirajan Shiwakoti, Peter Stansinopoulos

In understudied regional railway operations, this study explores passenger boarding and alighting patterns and how station design impacts them, particularly dwell times. Despite extensive metropolitan and suburban train research, regional railways have been overlooked. This study investigates regional rail passenger flow and dwell time to bridge this gap. This article studies dwell times and passenger boarding and alighting at two regional stations in Victoria, Australia, using CCTV data. The objective is to identify insights that might improve regional railway services' efficiency and user experience and advocate for sector-specific solutions. Analysis indicates distinct station boarding and alighting features, highlighting the discovery of the ‘blinded phenomenon’ for train conductors particularly in the afternoon peak (PMP). The results of the study showed that PMP services, which prioritise alighting passengers, had higher dwell times than the morning peak (AMP) services, which emphasise boarding passengers. Obstructed views make it difficult for train conductors to monitor passenger alighting, prolonging dwell times. Better human resource strategies, artificial intelligence for crowd surveillance, and strategic CCTV system deployment to streamline operations and improve passenger experience on regional railways are proposed in the paper, laying the groundwork for future research and operational changes in this vital transportation sector.

在研究不足的地区铁路运营中,本研究探讨了乘客上下车模式以及车站设计如何影响乘客上下车,尤其是停留时间。尽管对大都市和郊区列车进行了广泛研究,但区域铁路一直被忽视。本研究调查了区域铁路的客流和停留时间,以弥补这一空白。本文利用闭路电视数据研究了澳大利亚维多利亚州两个地区车站的停留时间和乘客上下车情况。目的是找出可提高地区铁路服务效率和用户体验的见解,并倡导针对具体行业的解决方案。分析表明了车站上下车的显著特点,重点发现了列车长的 "失明现象",尤其是在下午高峰时段(PMP)。研究结果表明,优先考虑下车乘客的 PMP 服务的停留时间高于优先考虑上车乘客的早高峰 (AMP) 服务。由于视线受阻,列车长难以监控乘客下车情况,从而延长了停留时间。本文提出了更好的人力资源战略、用于人群监控的人工智能以及战略性闭路电视系统部署,以简化区域铁路的运营并改善乘客体验,为这一重要交通部门的未来研究和运营变革奠定了基础。
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引用次数: 0
Modeling of impact of operations and maintenance on safety, availability, capacity, and cost of Railways-A System dynamics approach 运营和维护对铁路安全、可用性、运力和成本影响的建模--系统动力学方法
IF 2.6 Q3 TRANSPORTATION Pub Date : 2024-07-08 DOI: 10.1016/j.jrtpm.2024.100463
Katleho R.M. Mafokosi , Jan-Harm C. Pretorius , Gopinath Chattopadhyay

the transport infrastructure, particularly the railway infrastructure plays a vital role in the delivery of freight and the transportation of people. The ability and reliability of the railway infrastructure to deliver goods and transport people are challenged by train derailments and collisions caused by infrastructure breakdowns. Lack of maintenance has been identified as one of the causes of infrastructure breakdowns leading to accidents. The current paper proposes that if the railway infrastructure safety, availability, capacity, and cost are modeled using system dynamics, the impact of infrastructure operation and maintenance on safety can be predicted more accurately. The paper follows systems thinking approach that aims to understand the railway infrastructure as a system, by defining the system structure, system component relationships, and system behavior. The impact on railway infrastructure is modeled using system dynamics by developing causal loop diagrams and stock and flow diagrams which define the system structure, and system component relationships, and models the system behavior of safety, availability, capacity, and cost.

运输基础设施,特别是铁路基础设施在货物运输和人员运输方面发挥着至关重要的作用。铁路基础设施运送货物和运送人员的能力和可靠性受到基础设施故障造成的列车脱轨和碰撞事故的挑战。缺乏维护被认为是基础设施故障导致事故的原因之一。本文提出,如果利用系统动力学对铁路基础设施的安全性、可用性、容量和成本进行建模,就能更准确地预测基础设施运营和维护对安全的影响。本文采用系统思维方法,旨在通过定义系统结构、系统组件关系和系统行为,将铁路基础设施理解为一个系统。通过绘制因果循环图、存量图和流量图来定义系统结构和系统组件关系,并对安全性、可用性、容量和成本等系统行为进行建模,从而利用系统动力学来模拟对铁路基础设施的影响。
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引用次数: 0
A mathematical model for a two-service skip-stop policy with demand-dependent dwell times 根据需求确定停留时间的双服务跳站政策数学模型
IF 2.6 Q3 TRANSPORTATION Pub Date : 2024-07-05 DOI: 10.1016/j.jrtpm.2024.100461
Rodolphe Farrando , Nadir Farhi , Zoi Christoforou , Alain Urban

This paper presents a discrete-event model for a mass-transit line operated with a two-service skip-stop policy while allowing for train dwell times to vary according to passengers’ demand volumes. The model is formulated by two mathematical constraints on the train’s travel and safe separation times that govern the train dynamics on the line. In addition, the model takes into account trains’ dwell times, which are affected by both the services offered by the operator and passenger demand. The model is written in the max-plus algebra, a mathematical framework that allows us to derive interesting analytical results, including the fundamental diagram of the line, which describes the relationship between the average train time headway (or frequency), the number of trains running on the line and the passenger travel demand. The paper also derives indicators that are capable of quantifying and, thus, assessing the impact of a skip-stop policy on passengers’ travel. Finally, the paper compares two different passenger demand profiles. Results show that long-distance passengers mainly benefit from skip-stop policies, while short-distance travelers may experience an increase in their travel time. For long-distance passengers, the increase in the waiting time is counterbalanced by the decrease in the in-vehicle time, leading to an overall decrease in total passenger travel time.

本文提出了一个离散事件模型,该模型适用于一条采用双班次跳站政策运营的公共交通线路,同时允许列车停留时间随乘客需求量的变化而变化。该模型由列车行驶时间和安全分离时间两个数学约束条件组成,这两个约束条件控制着线路上的列车动态。此外,该模型还考虑了列车的停留时间,而列车的停留时间受运营商提供的服务和乘客需求的影响。该模型是用 max-plus 代数编写的,这一数学框架使我们能够得出有趣的分析结果,包括线路的基本图,它描述了列车平均间隔时间(或频率)、线路上运行的列车数量和乘客出行需求之间的关系。本文还得出了一些指标,这些指标能够量化跳站政策对乘客出行的影响,从而对其进行评估。最后,本文比较了两种不同的乘客需求状况。结果显示,长途乘客主要受益于跳站政策,而短途乘客的旅行时间可能会增加。对于长途乘客来说,等待时间的增加被车内时间的减少所抵消,从而导致乘客总旅行时间的总体减少。
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引用次数: 0
Formulation of train routing selection problem for different real-time traffic management objectives 针对不同实时交通管理目标的列车路由选择问题表述
IF 3.7 Q3 TRANSPORTATION Pub Date : 2024-06-14 DOI: 10.1016/j.jrtpm.2024.100460
B. Pascariu , M. Samà , P. Pellegrini , A. D’Ariano , J. Rodriguez , D. Pacciarelli

The train routing selection problem (TRSP) addresses the optimized selection of alternative routes as a preliminary step for real-time railway traffic management problem (rtRTMP). In the TRSP, route selection relies on estimating potential delays resulting from scheduling decisions. The selected routes are then exclusively applied in the rtRTMP. While prior research established the mathematical model and solution algorithms for the TRSP, its practical application in real-time rail traffic management remains limited. The existing TRSP model focuses on a single objective function for the rtRTMP. However, in practice, various stakeholders may prioritize different objectives, leading to diverse objective functions employed in the rtRTMP. This paper extends the TRSP model by considering a range of suitable objectives for the rtRTMP. We formulate the TRSP for each objective function and enhance the cost estimation model to evaluate the correspondence between the TRSP and rtRTMP objective functions. We then assess the overall effectiveness of the TRSP for the rtRTMP through an evaluation that takes into account several configurations of the model and the rtRTMP solution approach used. Our purpose is to enlarge the applicability of the TRSP and enhance the efficiency of the rtRTMP for real-world systems. The paper includes an in-depth computational analysis of two French case studies to investigate the performance of the TRSP across different rtRTMP configurations.

列车路线选择问题(TRSP)解决了作为实时铁路交通管理问题(rtRTMP)第一步的备选路线优化选择问题。在 TRSP 中,路线选择依赖于对调度决策导致的潜在延误进行估计。然后,选定的路线将专门应用于 rtRTMP。虽然先前的研究建立了 TRSP 的数学模型和求解算法,但其在实时轨道交通管理中的实际应用仍然有限。现有的 TRSP 模型重点关注 rtRTMP 的单一目标函数。然而,在实际应用中,各利益相关方可能会优先考虑不同的目标,从而导致轨道交通实时管理计划采用不同的目标函数。本文扩展了 TRSP 模型,为 rtRTMP 考虑了一系列合适的目标。我们为每个目标函数制定了 TRSP,并改进了成本估算模型,以评估 TRSP 与 rtRTMP 目标函数之间的对应关系。然后,我们通过考虑模型的几种配置和所使用的 rtRTMP 解决方法,评估 TRSP 对 rtRTMP 的整体有效性。我们的目的是扩大 TRSP 的适用性,提高 rtRTMP 在实际系统中的效率。本文包括对两个法国案例研究的深入计算分析,以研究 TRSP 在不同 rtRTMP 配置下的性能。
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引用次数: 0
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Journal of Rail Transport Planning & Management
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