突发事件下高速铁路列车运行调整研究

列车运行调整属于大规模的组合优化问题,其约束条件多,求解复杂,而突发事件下运行调整难度进一步加大。基于高速铁路采用的准移动闭塞制式,综合考虑列车区间运行时间、发车时间、停站时间、车站到发线数量以及追踪间隔时间等约束,以所有列车的总延误时间最小为目标,建立突发事件下的列车运行调整优化模型,利用具有动态变化惯性权重的粒子群算法求解模型。分析表明:突发事件下的列车运行调整优化模型及算法可以满足突发事件下高速铁路列车运行调整的时效性要求;动态变化惯性权重的粒子群算法具备较快的收敛速度与较强的局部挖掘能力。     

Tactical crew planning in railways

Tactical crew capacity planning problem in railways involves finding the minimum number of crews in a region required to operate a predetermined set of train duties satisfying the strict day-off requirement for crew. For the single-region problem, we develop two solution approaches based on a space–time network representation: the sequential approach and the integrated approach. We also study the multi-regional capacity planning problem where we minimize total system-wide capacity by simultaneously considering multiple regions within a neighborhood search algorithm based on our solution methods for the single-region problem. We present the computational study on problem instances from Turkish State Railways.     

铁路旅客列车车底套用优化模型的研究

在列车车底数量有限的条件下,利用多商品网络流模型对列车车底的套用问题建立数学优化模型,对车底套用方案进行优化,即把列车运行图转化为网络图,而后根据流守恒、容量限制和维修等约束条件,建立以列车运输能力最大化为目标的整数规划模型。     

Perspectives for a future high-speed train in the Swedish domestic travel market

Gröna tåget (the Green Train) is a research and development project with the aim to develop a high-speed tilting train concept for the Swedish and Nordic markets. Competition with other modes needs to be evaluated, especially as regards travelling times and fares, with special attention paid to domestic airlines.For new trains, gains in travelling times and lower operational costs can be expected. Model calculations of operational costs for domestic air stages and high-speed trains, respectively, show that high-speed trains have lower costs per available seat kilometer. Train operators can meet competition with fares from coaches and air carriers provided they introduce yield management. The primary competition is about travelling times. Gröna tåget would increase the train’s attractiveness and win over some travel from airlines.     

A matheuristic approach to the air-cargo recovery problem under demand disruption

Air cargo transport is subject to unpredictable changes in expected demand, necessitating adjustments to itinerary planning to recover from such disruptions. We study a flight rescheduling problem to react to cargo demand disruptions in the short run. To increase flexibility, we consider two different cargo assignment policies. We propose a matheuristic approach to solve the problem that provides high-quality solutions in a short computational time, based on column generation in which each subproblem is solved using an ad-hoc heuristic. The approach is tested on demand disruption instances containing up to 75 air cargo orders with different penalty levels. The results show that the proposed method improves profit by 54% over the solution generated by a commercial MIP solver within a 1-h time limit, and by 15% over the solution with the routes fixed as in the original flight planning that only allows cargo to be re-routed. We also show that there exist incremental benefits in the range of 3–5% by allowing cargo for a given order to be transported by various aircraft.     

An exact solution approach for vehicle routing and scheduling problems with soft time windows

A new column generation based exact optimization approach for the vehicle routing and scheduling problem with semi soft time windows (VRPSSTW) is presented. Elementary shortest path problem with resource constraints and late arrival penalties is solved as a subproblem, which rises from the Dantzig–Wolfe decomposition method. Exact solutions of VRPSSTW and hard time windows variant are compared on Solomon’s benchmark instances as well as on an instance based on Tokyo road network. It was found that the VRPSSTW solution results in fewer routes thus overall costs are reduced and late arrival penalties contribute only a small fraction to total cost.     

乘务员运用计划编制模型与计算方法的研究

分析铁路在轮乘制方式下编制乘务员运用计划的方法，提出以运行图为基础数据，建立乘务日计划编制的多目标数学模型，运用回溯搜索算法对模型进行求解，并给出了算法的基本步骤。以京沪高速铁路为例，将研究成果运用于列车服务信息系统的乘务子系统中，验证了模型与算法的正确性。     

Railway crew capacity planning problem with connectivity of schedules

We study a tactical level crew capacity planning problem in railways which determines the minimum required crew size in a region while both feasibility and connectivity of schedules are maintained. We present alternative mathematical formulations which depend on network representations of the problem. A path-based formulation in the form of a set-covering problem along with a column-and-row generation algorithm is proposed. An arc-based formulation of the problem is solved with a commercial linear programming solver. The computational study illustrates the effect of schedule connectivity on crew capacity decisions and shows that arc-based formulation is a viable approach.     

青藏铁路格拉段货物列车开行方案

根据青藏铁路格拉段特殊的自然、经济条件和铁道第一勘察设计院提供的车流量预测资料,结合实际运营经验,编制出区段重空车流斜表,再根据列车牵引重量和各区间的车流量,确定管内列车的行车量,从而编制格拉段的货物列车开行方案。     

Freight train scheduling with elastic demand

A train slot selection model based on multicommodity network flow concepts is developed for determining freight train timetables for scheduling rail services along multiple interconnected routes. The model seeks to minimize operating costs incurred by carriers and delays incurred by shippers while ensuring that the schedules and demand levels are mutually consistent. A column generation-based methodology is proposed for train slot selection to meet frequency requirements. This methodology is embedded in a simulation-based iterative framework, where demand for rail services is re-computed in accordance with the train schedule obtained by solving the freight train scheduling problem.     

基于列生成的高速铁路车站作业计划调度调整方法研究

大型高速铁路车站到发线及列车进路的冲突是调度调整的重点,为了提高调整效率和效果,在将问题抽象为时空网络上多商品流的基础上,考虑技术作业要求、作业间隔时间、线路和进路运用规则等约束条件,以列车总晚点时间小、旅客便捷性好为目标,构建集到发线、咽喉进路和到发时刻为一体的车站作业调度调整0-1整数规划模型。针对调度调整的强实时性,设计基于列生成的求解算法,并以长春西站为例进行验证。结果表明,该方法可在较短时间内得到满意的车站作业计划调整方案。     

A carrier’s optimal bid generation problem in combinatorial auctions for transportation procurement

We consider the carrier’s optimal bid generation problem in combinatorial auctions for transportation procurement. Bidders (carriers) employ vehicle routing models to identify sets of lanes (origin-destination pairs) based on the actual routes that a fleet of trucks will follow in order to maximize profit. Routes are constructed by optimally trading off repositioning costs of vehicles and the rewards associated with servicing lanes. The carrier optimization represents simultaneous generation and selection of routes and can incorporate any existing commitment. We employ both column generation and Lagrangian based techniques for solving the carrier optimization model and present numerical results.     

基于MapX的旅客列车开行路径优化设计

在旅客列车开行效益分析与优化辅助决策系统中,通过电子地图技术集成实现旅客列车开行路径的可视化优化设计。在论述系统结构的基础上,对电子地图的建立、基本功能、开行路径设计进行了具体描述,并利用计算机自动计算方式对太原—徐州的列车开行路径进行了应用仿真,说明系统方法的可行性和高效性。     

A comparison of two exact methods for passenger railway rolling stock (re)scheduling

The assignment of rolling stock units to timetable services in passenger railways is an important optimization problem that has been addressed by many papers in different forms. Solution approaches have been proposed for different planning phases: strategic, tactical, operational, and real-time planning. In this paper we compare two approaches within the operational and real-time planning phase. The first exact approach is based on a known Mixed Integer Linear Program (MILP) which is solved using CPLEX. The second approach is a new method that is an extension of a recently introduced MILP, which is solved using a column and row generation approach. In this paper, we benchmark the performance of the methods on networks of two countries (Denmark and The Netherlands). We use the approaches to make daily schedules and we test their real time applicability by performing tests with different disruption scenarios. The computational experiments demonstrate that both models can be used on both networks and are able to find optimal rolling stock circulations in the different planning phases. Furthermore, the results show that both approaches are sufficiently fast to be used in a real-time setting.     

双线铁路列车调度阶段计划自动调整的遗传算法

列车运行调整是一类NP完全问题,在借鉴国内外专家对铁路列车运行自动调整研究成果的基础上,建立双线铁路列车调度阶段计划自动调整数学模型,并给出相关约束表达式。根据遗传算法原理,对阶段计划自动调整模型进行优化,采用罚函数法对约束条件进行处理,建立基于惩罚函数的适应度函数,采用交叉、变异等技术给出遗传算法的基本求解步骤。     

The European high-speed train network: Predicted effects on accessibility patterns

The principal aim of this paper is to evaluate the impact of the future European high-speed train network on accessibility, by reducing time distance between places and modifying their relative location. We compare the current situation with that foreseen for the year 2010, according to the Outline Plan of the European High-Speed Train Network, in order to analyse which areas will most benefit from construction and improvement of the infrastructure. It is hypothesized that the high-speed train will certainly bring the peripheral regions closer to the central ones, but will also increase imbalances between the main cities and their hinterlands. A weighted average distance indicator is applied for this purpose. This measure identifies the spatial distribution of accessibility in the area of study, emphasizing the infrastructure effects, and locates accessibility changes at the European level. A Geographic Information System (GIS) has been used to carry out this study.     

具有能力限制的路网重车流径路优化方法

通过对铁路车流径路的描述和现行优化方法的分析,建立一种在满足运输要求的前提下,使运输费用最小的车流径路优化模型。为使目标函数尽快地趋向满意解,对车流排列序数的初始赋值方法及调整方法进行了设计。以现行“华东铁路网径路图”及运营数据为依据,进行车流径路计算,取得了满意的径路方案。     

铁路列车编组计划优化系统设计

对计算机编制列车编组计划系统从数据及参数处理、车流结构调整、专家干预和智能优化等4个方面进行了分析，对优化列车编组计划的参数确定，给出了相应的理论公式和实际运作中可行的经验取值方法。同时介绍了系统的专家决策和干预系统，以及智能编组计划模块。该优化系统为济南铁路局编制管内列车编组计划提供了依据。     

高速铁路可变编组列车开行计划优化

目前,我国高速铁路列车一般采用固定编组形式,动车组运用效率较低,而未来可变编组列车投入使用后,运营组织方式将发生很大变化,需要优化列车开行计划以充分发挥可变编组列车的优势。研究可变编组列车在各技术区段的编组内容和组合拆解计划,以动车组开行成本最小和组合拆解作业时间最短为优化目标,构建可变编组列车开行计划优化模型,设计分支定界算法求解。以京沪高速铁路进行案例分析,结果表明:相比同等条件下固定编组模式,优化的可变编组列车开行计划可以提高列车客座利用率。     

合理接续条件下旅客列车开车时刻研究

在分析接续列车到达时刻协调性的基础上,引入合理接续条件的概念,运用同余理论从多列换乘接续列车的可达性和合理性方面构造多列车换乘衔接模型,界定各方向列车的合理开车时刻。以青藏铁路旅客列车为例,在采用季节性旅客列车开行方案的基础上,模拟验算各方向列车的发车时间范围,说明算法模型计算过程比较简单,但对于实际列车的开行需要进行综合统筹,才能达到满意的效果。