Estimation method for a skip-stop operation strategy for urban rail transit in China

The skip-stop operation strategy （SOS） is rarely applied to Chinese urban rail transit networks because it is a simple scheme and a less universally popular transportation service. However, the SOS has performance advantages, in that the total trip time can be reduced depending on the number of skipped stations, crowds of passengers can be rapidly evacuated at congested stations in peak periods, and the cost to transit companies is reduced. There is a contradiction between reducing the trip time under the SOS and increasing the passengers＇ waiting times under an all-stop scheme. Given this situation, the three objectives of our study were to minimize the waiting and trip times of all passengers and the travel times of trains. A comprehensive estimation model is presented for the SOS. The mechanism through which the trip time for all passengers is affected by the SOS is analyzed in detail. A 0-I integer programming formulation is established for the three objectives, and is solved using a tabu search algorithm. Finally, an example is presented to demonstrate that the estimation method for the SOS is capable of optimizing the timetable and operation schemes for a Chinese urban rail transit network.

Modified stochastic user-equilibrium assignment algorithm for urban rail transit under network operation

Based on the framework of method of successive averages(MSA), a modified stochastic user-equilibrium assignment algorithm was proposed, which can be used to calculate the passenger flow distribution of urban rail transit(URT) under network operation. In order to describe the congestion's impact to passengers' route choices, a generalized cost function with in-vehicle congestion was set up. Building on the k-th shortest path algorithm, a method for generating choice set with time constraint was embedded, considering the characteristics of network operation. A simple but efficient route choice model, which was derived from travel surveys for URT passengers in China, was introduced to perform the stochastic network loading at each iteration in the algorithm. Initial tests on the URT network in Shanghai City show that the methodology, with rational calculation time, promises to compute more precisely the passenger flow distribution of URT under network operation, compared with those practical algorithms used in today's China.

Optimization method of urban rail train operational plan based on O-D time-varying demand

Purpose–Under the constraints of given passenger service level and coupling travel demand with train departure time,this study optimizes the train operational plan in an urban rail corridor to minimize the numbers of train trips and rolling stocks considering the time-varying demand of urban rail passenger flow.Design/methodology/approach–The authors optimize the train operational plan in a special network layout,i.e.an urban rail corridor with dead-end terminal yard,by decomposing it into two sub-problems:train timetable optimization and rolling stock circulation optimization.As for train timetable optimization,the authors propose a schedule-based passenger flow assignment method,construct the corresponding timetabling optimization model and design the bi-directional coordinated sequential optimization algorithm.For the optimization of rolling stock circulation,the authors construct the corresponding optimization assignment model and adopt the Hungary algorithm for solving the model.Findings–The case study shows that the train operational plan developed by the study’s approach meets requirements on the passenger service quality and reduces the operational cost to the maximum by minimizing the numbers of train trips and rolling stocks.Originality/value–The example verifies the efficiency of the model and algorithm.

Analysis of STC Fault in Urban Rail Transit Station of Mobile Block System

Mobile block system is a new type of block technology based on the theory of interval block. This article focuses on the analysis of safety key points, the efficient use of emergency time, the maximum efficiency of mobilizers, to reduce the loss of emergency incidents and casualties.

Optimization of Telephone Occlusion Method on Urban Rail Transit in Shanghai

Telephone occlusion method is a backup manual occlusion method during an urban rail transit signal equipment failure, which ensures that metro operated safely and orderly. Through the results of several telephone occlusion exercises, find out the shortcomings oftclcphone occlusion method and optimizing it.

Study on the Evaluation of the New Line of Urban Rail Transit Based on Analytic Hierarchy Process

The basic conditions of Urban rail transit line test operation are mainly based on Basic condition for trial operation of urban rail transit （GB/T30013-2013） the basic conditions of the relevant provisions, but the status and standard of trial operation of the basic conditions for assessment of the operating departments are still inadequate, during the three mouth of trial running operations, the specific work of trial operation and exercise are not clear about what this study focuses. This study emphasizes on the methods of operation assessment, through the Analysis Hierarchy Process （AHP） to make the commissioning work carry out smoothly and effectively, making the running exercise Rally, and the emergency and safety follow-up operation process can be quickly handled properly, and it is also helpful to the sustainable development of urban raft transit.

Research of BIM Technology in Urban Rail Operation and Maintenance and Application

With the rapid development of urban rail transit,the traditional operation and maintenance methods mainly rely on manpower,and the pressure on equipment operation and maintenance is increasing,and the low work efficiency,high intensity and high operating costs have always been the main problems at this stage.Through BIM visualization technology can effectively solve those problems,the operation and maintenance mode of urban rail signal equipment at this stage is discussed,the integration and visualization of BIM technology are used to make the judgments and early warnings on the maintenance of urban rail signal equipment,and play a positive and important role in operation and maintenance work,this research result can provide ideas and references for urban rail transit operation and maintenance in the new era.

Integrated Optimization of Timetable and Rolling Stock Circulation under Mixed Usages of Short-length and Full-length Services in Urban Rail Transit

The rapid growth of passenger flow in urban rail transit has led to great service pressures for metro companies in organizing train services to provide higher transportation capacities in order to satisfy passengers' travel demand, especially on those metro lines with insufficient rolling stock. In order to cope with high passenger flow service pressure, a mixed integer nonlinear programming(MINLP) model is proposed to optimize the line plan, timetable and rolling stock circulation simultaneously, to reduce the number of rolling stocks and increase the number of full-length services. A two-step algorithm strategy is proposed. In the first stage, the train timetable is optimized under the assumption that all the train services are the full-length services. In the second stage, the rolling stock plan is optimized based on the timetable optimized in the first stage. To ensure a feasible rolling stock circulation, certain full-length services are shortened to the short-length services due to the limited number of rolling stocks. Numerical experiments are performed based on the real-life data of Shanghai Metro Line 8. Results show that the proposed method can efficiently optimize the timetable and rolling stock circulation of the whole operation day. The optimized results are beneficial for both the service and the operational costs.

Research on Multi-Objective Real-Time Optimization of Automatic Train Operation(ATO) in Urban Rail Transit

The determination and optimization of Automatic Train Operation(ATO) control strategy is one of the most critical technologies for urban rail train operation. The practical ATO optimal control strategy must consider many goals of the train operation, such as safety, accuracy, comfort, energy saving and so on. This paper designs a set of efficient and universal multi-objective control strategy. Firstly, based on the analysis of urban rail transit and its operating environment, the multi-objective optimization model considering all the indexes of train operation is established by using multi-objective optimization theory. Secondly, Non-dominated Sorting Genetic Algorithm II(NSGA-II) is used to solve the model, and the optimal speed curve of train running is generated.Finally, the intelligent controller is designed by the combination of fuzzy controller algorithm and the predictive control algorithm, which can control and optimize the train operation in real time. Then the robustness of the control system can ensure and the requirements for multi-objective in train operation can be satisfied.

The Trackless Tram: Is It the Transit and City Shaping Catalyst We Have Been Waiting for?

Recent innovations in transport technology are now providing mobility that is cheaper, autonomous, electric, and with improved ride quality. While much of the world’s attention has been on how this can be applied to cars, there have been rapid adoption of these and other technologies in High Speed Rail and Metro Rail systems that run between and across cities. This paper shows how such innovations have now been applied to create the next generation of urban transit system called a Trackless Tram. Trackless Trams are effectively the same as traditional light rail except they run on rubber tyres avoiding disruption from construction for Light Rail, but they retain the electric propulsion (with batteries) and have high ride quality due to rail-type bogies, stabilization technologies and precision tracking from the autonomous optical guidance systems—with infrastructure costs reduced to as low as one tenth of a Light Rail system. As with Light Rail, a Trackless Tram System provides a rapid transit option that can harness the fixed route assurance necessary to unlock new land value appreciation that can be leveraged to contribute to construction and running costs whilst creating urban regeneration. The paper considers the niche for Trackless Trams in cities along with its potential for city shaping through the creation of urban re-development along corridors. The paper suggests that the adoption of Trackless Tram Systems is likely to grow rapidly as a genuine alternative to car and bus systems, supplementing and extending the niche occupied by Light Rail Transit (LRT). This appears to be feasible in any medium-sized or larger city, especially in emerging and developing economies, and case studies are outlined for Perth and Thimpu to illustrate its potential.

跨线条件下城市轨道交通列车交路计划优化方法

跨线运营是城市轨道交通重点发展方向。针对跨线条件下列车交路计划编制问题,通过构造乘客出行时空网络图准确刻画复杂交路下的客流行为,建立以最小化列车走行公里与乘客出行时间成本为目标的混合整数规划模型。模型以列车交路方案、开行比例与频率为决策变量,并针对跨线交路与本线交路的行车冲突,考虑非等间隔发车,确定列车发车时刻。设计基于交路及开行频率搜索与运行间隔协调的定制分解算法。案例结果表明,列车跨线方向与乘客换乘主方向一致时,跨线交路可同时提升企业运营与乘客出行效益。换乘出行导致的断面客流量差异是跨线交路开行方案设置的主要依据。研究结论可为运营企业制定列车交路计划提供依据,有助于提高网络运输效率。

基于车车通信列控系统的城市轨道交通列车运行效率分析

[目的]城市轨道交通T2T(车车通信)列控系统是一种新型的信号系统,其通过资源化管理方式对轨旁设备进行管控。为了验证该系统的优越性,需对该系统下的列车运行效率进行分析。[方法]针对T2T列控系统,基于资源管理层面和安全防护原理的特点,在折返工况下,将原本由联锁控制的双动道岔转变为两个单动道岔,并基于列车精确自定位实现ATP(列车自动防护),提高了岔区线路资源的使用能力;在区间和车站追踪工况下,通过前后车对于车速、加速度、所处线路位置等信息的实时互传,利用相对速度安全防护原理进一步缩小了列车的追踪间隔。通过上述两方面的技术革新,结合城市轨道交通线路的实际数据,对站后交叉渡线折返、站前单渡线折返、区间与车站追踪等运营场景进行了模拟仿真计算,确定了T2T列控系统的折返能力和区间追踪能力。[结果及结论]相较传统的CBTC(基于通信的列车控制系统),T2T列控系统在折返能力、追踪能力等方面均有着显著提升,更加适应于超大运量的城市轨道交通线路;T2T列控系统架构简单,轨旁设备少,尤其适合城市轨道交通的大修改造项目。

城市轨道交通企业财务表现能力研究

[目的]为了系统性地把握企业财务状况,提升城市轨道交通企业的经营决策能力,需研究城市轨道交通企业的财务表现能力。[方法]从营业总成本、盈利能力、偿债能力、营运能力和成长能力五个方面,统计分析了我国10座城市的轨道交通企业的营业总成本及人工成本、偿债能力比率、盈利能力比率、营运能力比率和成长能力比率,并基于此研究了企业的财务表现能力。[结果及结论]天津地铁存量PPP(公私合营)项目盘活资金超150亿元,减轻了政府债务负担。其他城市的轨道交通企业的营业总成本和人工成本整体呈上升趋势,建议通过PPP模式来减轻政府财务压力,提高成本效率。北京、成都、武汉、青岛、南京的轨道交通企业的长期偿债能力较弱。针对2021年成都、武汉、南京的轨道交通企业的负债程度偏高问题,建议采取光伏发电、地源热泵、共享车辆基地、设备国产化等措施减少企业成本。对于企业盈利偏低问题,建议通过提供运营服务咨询、运营管理服务等方式增加收入。

城市轨道交通全自动运行线路多专业速度控制与匹配设计研究

城市轨道交通多专业间的协调性是决定能否充分实现预期能力、发挥投资效益的关键环节,列车运行速度是其中一个重要方面,是城市轨道交通技术装备、技术标准、运营管理水平的重要标志。针对不同专业速度控制存在的重叠防护问题,通过剖析通信、信号、车辆、线路、环境等对全自动运行(FAO)线路列车运行速度的限制,提出列车自动运行(ATO)模式、列车自动防护(ATP)模式、蠕动模式和洗车模式4种典型运行模式下的速度匹配控制方案,讨论了根据线路等级速度拟定正线区间结构设计速度、车辆构造速度、车辆超速防护触发速度、车辆最大动态包络线计算速度、最高ATP顶篷速度、最高ATO目标速度的方法,并给出多专业匹配设计关键速度建议值。同时借助仿真手段,结合不同站间距设置与最短时间速度曲线计算,进一步针对速度等级为80,100 km/h以及120 km/h的线路分别讨论了站间距的匹配设计,建议三者站间距分别不少于1.0,1.4 km以及2.5 km。开展多专业速度控制与匹配设计的优化,有助于最大化发挥系统和设备性能,保证线路整体运营水平。

城市轨道交通工程防淹能力评估方法研究

近年来我国城市轨道交通工程水淹事件频发,人民生命财产安全受到威胁。交通运输部在2022年7月修订的《城市轨道交通初期运营前安全评估管理办法》中增加了“工程项目防洪专项论证报告等材料”作为轨道交通新线投入初期运营前的前提条件之一,因此开展城市轨道交通工程防淹能力研究十分必要和紧迫。本文从外部风险、基础防汛能力、防汛预警能力、应急救援能力等方面研究了影响城市轨道交通工程防淹能力的关键因素,利用专家打分法、层次分析法构建了评估指标体系及其权重系数,并根据我国现行法律法规标准规范提出了各指标评分细则,建立了城市轨道交通运营线路防淹能力评估方法,以期为我国汛期城市轨道交通运营安全提供技术支撑。

基于组合赋权-可拓云的城市轨道交通线路运营安全评价

为解决城市轨道交通运营安全评价指标缺乏时效性和部分安全评价模型忽略评价等级的模糊界限等问题,重新构建城市轨道交通线路的运营安全评价指标体系,包括员工对传染性疾病防控措施的执行力度、相关单位的配合程度、防控设备的完备程度等新指标;其次运用基于离差最小化的最优最劣法(BWM)和反熵权法对各指标进行组合赋权;然后应用可拓云确定城市轨道交通线路运营安全评价等级;最后以上海地铁17号线为例进行实例分析。结果表明:上海地铁17号线运营安全评价各指标的各级云关联度低于0.5且置信度高于0.99,其中,人员因素、线路因素、管理因素的置信度均为1,仅设备因素的置信度为0.998;结合每个二级指标的灵敏度值分析,得出车站运营设备的可靠性对线路实际运营安全影响最大;在实际运营中,乘客对车站传染性疾病防控的配合程度越高,对综合评价的提升也越大;该评价指标体系和评价模型能够准确地反映城市轨道交通线路运营安全水平,且更加适用于目前城市轨道交通线路的运营情况。

城市轨道交通乘务交路方案编制的禁忌搜索优化方法

针对城市轨道交通普遍采用轮乘制、日班和两头班混合等特点,对城市轨道交通乘务交路方案编制问题进行研究,旨在降低乘务成本并提高乘务效率.首先,通过分析城市轨道交通乘务交路方案的构成要素,考虑值乘时长、值乘片段接续时间和接续地点等要求,构建值乘片段、值乘任务构成和乘务规则约束,由此建立以乘务组数量和总接续时间等综合指标最小化为目标函数的多目标0-1整数规划模型.然后,针对该模型设计禁忌搜索(Tabu Search,TS)算法进行求解,以先到先走(First-In-First-Out,FIFO)的就近指派原则得到初始解,并设计4种邻域变换策略,以提高邻域解的多样性,并构建基于多邻域结构的禁忌搜索求解算法,实现对乘务交路方案的优化.最后,以广州地铁7号线的乘务交路方案为例进行实例验证.研究结果表明:优化方案较实际运营方案的乘务作业段数和总接续时间分别降低了20%和4.94%,每个乘务作业段值乘列车数量从8.2列增加到10.3列,有效驾驶时间从5.4 h增加到5.8 h,优化方案的各项指标均得到显著提升.研究成果可以为城市轨道交通乘务计划编制提供理论和方法支持.

城市轨道交通线网客流管控系统设计及实现

为提高轨道交通运营企业抵御大客流风险的能力,设计研发城市轨道交通线网客流管控系统。面向客流调度员的实际业务需求,设计管控方案管理、方案智能编制、方案预评估、方案后评估等4项核心功能,通过动态客流分配、客流控制算法等技术,对线网级客流进行科学化、智能化、全流程管理。该系统已在北京地铁试点应用,应用表明,该系统弥补了既有经验式管理的不足,提高了客流安全风险防控水平,能够为智能化运营管理提供技术支持。

基于效用理论的城市轨道交通运营管理优化策略

在城市轨道交通运营的过程中,运营企业为了开展有效的管理工作,需要对交通客流的形成进行全面的分析,在此基础上了解交通出行的需求、出行方式的选择,提出了交通需要和交通需求之间的重要联系,指出交通出行方式的选择和出行者的支付能力,效用最大化之间具有一定的关联。使用了效用理论,建立了交通分担的模型,分析了城市轨道交通和其他交通方式所形成的竞争机制。研究主要分析的是天津市的城市轨道交通,对于交通客流的形式和特征进行了完善的研究。研究的结果是:交通运输资源的利用和客流量具有重要的联系,客流量多,资源能够全面地利用,客流量少,资源不能实现全面的应用。为了有效地利用资源,实现企业经济收益的最大化,需要利用效用理论,对票价、发车的时间等进行调整,不同的时间段和客流量,使用不同的运营管理策略,有效地提高企业经营和管理的效率。

基于滑模控制的虚拟编组列车追踪控制策略

[目的]现有的基于移动闭塞的列车控制系统中,相邻列车之间存在较大的安全裕度,在面对潮汐客流现象时,区段的运输效率同区段的实际运力需求无法匹配。虚拟编组列车能够提高线路的运力,同时能更好地适应不平衡的通勤客流。因此,需研究适用于虚拟编组列车的高精度追踪控制策略。[方法]针对虚拟编组列车运行控制问题,提出了一种基于滑模控制的虚拟编组运行控制策略。建立了列车动力学模型和虚拟编组列车运行控制模型;设计了非奇异终端滑模控制器,并对所设计的控制器进行了仿真测试。[结果及结论]在所提出的虚拟编组控制策略下,虚拟编组列车的位置跟踪误差和速度跟踪误差能够沿滑模面在有限时间内渐近收敛到零。在仿真验证的4列列车中,当首列列车运行状态发生改变时,虚拟编组中的其余列车会在很短的时间内跟踪期望的速度轨迹,验证了所提出的控制策略对虚拟编组列车追踪控制的有效性。