Integrating Timetabling and Crew

We investigate to what degree we can integrate a Train Timetabling / Engine Scheduling Problem with a Crew Scheduling Problem. In the Timetabling Problem we design a timetable for the desired lines by fixing the departure and arrival times. Also, we allocate time-slots in the network to secure a feasible timetable. Next, we assign engines in the Engine Scheduling Problem to the lines in accordance with the timetable. The overall integration is achieved by obtaining an optimal solution for the Timetabling / Engine Scheduling Problem. We exploit the fact that numerous optimal, and near optimal solutions exists. We consider all solutions that can be obtained from the optimal engine schedule by altering the timetable, while keeping the order of demands in the schedules intact. The Crew Scheduling model is allowed to re-time the service of demands if the additional cost is outweighed by the crew savings. This information is implemented in a mathematical model for the Crew Scheduling Problem. The model is solved using a column generation scheme. Hereby it is possible for the Crew Scheduling algorithm to adjust the timetable and achieve a better overall solution. We perform computational experiments based on a case at a freight railway operator, DB Schenker Rail Scandinavia, and show that significant cost savings can be achieved

Bexley report: a report to MCCH on a suitable transport policy for its Bexley services

This report presents the findings of and recommendations from the study commissioned by MCCH to advise on a comprehensive transport policy for MCCH to use in providing services in both its residential homes and day-care centres in Bexley. It describes the current positions of transport supply for, and of transport demand by the community of people with learning difficulties in the London Borough of Bexley. It also considers the extent to which the transport supply is meeting or not meeting the transport demands and the expressed needs of the people and/or their representatives. The report considers the implications for improvement in transport provision of certain proposed actions by MCCH. Finally, the report presents some recommendations based on a user-centred strategy to help MCCH incorporate their concept of empowering their service users through suitable transport provision. This study has been conducted with the ethos and operational objectives of the MCCH group firmly in mind. MCCH has an objective to enhance quality of life for their service users and is very concerned with ensuring that its service users are enabled to exercise the rights and opportunities of citizenship with particular reference to freedom of choice in time and mode of travel. MCCH holds that real improvement in services to learning disability people must include increased range and choice of people-centred opportunities that address the total needs and aspirations of service users and their carers, underpinned by values and principles of good practice. Thus MCCH desires to put back in the control of users, the lever of decision making as regards services provided to 4 them and intends to do this by actively eliciting user/stakeholders involvement in decision-making. Contrary to the standard social service transport provision style, MCCH desires to create choice for service-users, feeling that people should be able to decide whether, e.g. to go by bus or train and be supported in their decision and not be constrained by the schedule of the provided transport. The specific terms of reference for this study are 1. To examine the current demand for, and provision of, transport within MCCH’s Bexley services. To assess how best these services might be reconfigured and managed, having regard to: · Desire to increase empowerment and choice for service users · Optimizing the integration of the transport management in Bexley within MCCH’s organization, in the light of most efficient use of resources and practice elsewhere in MCCH · Desire to better integrate residential services with day services in Bexley · MCCH’s intention to reconfigure Bexley day services · The move of service users towards ‘supported living’ as opposed to registered care · The objectives and concerns of all parties involved, including Bexley Social Services, Bexley Transport Services, the parents/relatives/carers of the service users and the service users themselves · The way vehicles are currently owned and funded · Efficiency and cost 2. To produce outline proposals, plans and specifications of how a reconfigured transport service would look and operate, including details of resource requirements in enough detail to allow reasonably accurate costing to be derived

Cyclic Timetable Scheduling Problem on High-speed Railway Line

Due to several obvious advantages both in transport marketing and train operation planning, the cyclic timetable has already applied in many high-speed railway (HSR) countries. In order to adopt the cyclic timetable in China's HSR system, a Mixed Integer Programmer (MIP) model is proposed in this paper involving many general constraints, such as running time, dwell time, headway, and connection constraints. In addition, the real-world overtaking rule that concerning a train with higher priority will not be overtaken by a slower one is incorporated into the cyclic timetable optimization model. An approach based on fixed departure is proposed to get a cyclic timetable with minimum total journey time within a reasonable time. From numerical investigations using data from Guangzhou-Zhuhai HSR line in China, the proposed model and associated approach are tested and shown to be effective

Crew Scheduling for Netherlands Railways: "destination: customer"

: In this paper we describe the use of a set covering model with additional constraints for scheduling train drivers and conductors for the Dutch railway operator NS Reizigers. The schedules were generated according to new rules originating from the project "Destination: Customer" ("Bestemming: Klant" in Dutch). This project is carried out by NS Reizigers in order to increase the quality and the punctuality of its train services. With respect to the scheduling of drivers and conductors, this project involves the generation of efficient and acceptable duties with a high robustness against the transfer of delays of trains. A key issue for the acceptability of the duties is the included amount of variation per duty. The applied set covering model is solved by dynamic column generation techniques, Lagrangean relaxation and powerful heuristics. The model and the solution techniques are part of the TURNI system, which is currently used by NS Reizigers for carrying out several analyses concerning the required capacities of the depots. The latter are strongly influenced by the new rules.crew scheduling;dynamic column generation;lagrange relaxation;railways;set covering model

Issues on simulation of the railway rolling stock operation process – a system and literature review

Railway traffic simulation, taking into account operation and maintenance conditions, is not a new issue in the literature. External effects in such networks (eg. level crossings) were not taken into account in studies. The used models do not take into account sufficiently the process of degradation and recovery of the network. From the technical side, currently carried out simulations are made using similar approaches and techniques as in the initial stage of research. Well-established work in this area could be the basis for evaluation of new solutions. However, the progress in simulation tools during the last years, especially in performance and programming architecture, attempt to create a modern simulation tool. In the paper were presented the main assumptions for the evaluated event-based simulation method, with application to stiff-track transportation network

The crew scheduling problem of an interurban public transport bus company

Una planificación de los conductores adecuada impacta en el coste operacional de las empresas de transporte público. La dificultad de esta tarea se debe principalmente a dos aspectos (Esclapés 2001, Bonrostro, Yusta 2003, Ernst et al. 2004, Van den Bergh et al. 2013, Ibarra-Rojas et al. 2015, Li et al. 2015): por un lado, la planificación de los conductores es parte de un problema mayor, la planificación de los vehículos y conductores. Por otro lado, las diferencias entre las características de las redes de transporte, los recursos de las empresas, las restricciones reglamentarias o los acuerdos laborales hacen que las soluciones sean particulares para cada empresa. El objetivo principal de esta investigación es desarrollar un algoritmo eficiente que minimice en un tiempo de ejecución aceptable el problema de la planificación de los conductores de una compañía de autobuses de transporte de pasajeros público interurbano, permitiendo relevos ilimitados en cualquier parada de la red, es decir, al principio, final o cualquier otra parada intermedia de una línea. De esta manera, haciendo uso de la herramienta en una empresa real, se han examinado dos lagunas de investigación encontradas en el análisis de la literatura. Por un lado, el impacto de permitir relevos ilimitados al principio, al final o en cualquier otra parada intermedia de una línea. Por otro lado, el impacto del proceso de planificación cuando las restricciones a cumplir varían según el tipo de servicio que se incluye en las jornadas. Se han analizado dos procesos: el dividir el problema en problemas independientes según las características de los servicios, o el llevar a cabo una planificación global bajo las restricciones más restrictivas. Con respecto a la metodología de investigación, se han seguido los siete pasos de la Investigación Operativa (Winston, Goldberg 2004): (1) formular el problema, (2) observar el sistema, (3) formular un modelo del problema, (4) verificar el modelo y usarlo para la predicción, (5) seleccionar una alternativa adecuada, (6) presentar los resultados y conclusiones del estudio e (7) implementar y evaluar las recomendaciones. Los resultados muestran que en ocasiones vale la pena considerar los factores investigados.Gidarien lanaren plangintza egoki batek zuzenki eragiten du garraio publikoko enpresen kostu operatiboan. Tripulazioaren plangintzaren zailtasuna bi arrazoiengatik ematen da bereziki (Esclapés 2001, Bonrostro, Yusta 2003, Ernst et al. 2004, Van den Bergh et al. 2013, Ibarra-Rojas et al. 2015, Li et al. 2015): alde batetik, gidarien plangintza beste arazo handiago baten parte da, ibilgailu eta gidarien plangintzaren arazoaren parte. Bestalde, garraio sareen arteko ezberdintasunek, enpresen baliabideen arteko ezberdintasunek edota arautegi edo lan-akordioen arteko ezberdintasunek, enpresa bakoitzarentzako soluzio partikular bat garatzea behartzen dute. Ikerketa honen helburu nagusia "algoritmo eraginkor bat garatzea da, zeinek exekuzio denbora apropos baten, eta lehen, azken edo beste edozein bitarteko geldialditan errelebua baimenduz, hiriarteko sare baten diharduen garraio publikoko autobus konpainia batek behar duen tripulazioa minimizatzen duen". Horrela, eta konpainia erreal baten tripulazioaren planifikazioa oinarritzat hartuta, literaturan aurkitutako bi ikerketa-hutsune aztertu dira. Alde batetik, zenbatetan mugatu ezak eta lehen, azken edo beste edozein bitarteko geldialditan errelebuak baimentzeak daukan inpaktua aztertuko da. Bestalde, planifikatzerakoan ezaugarri ezberdinak dituzten zerbitzuek errestrikzio ezberdinak kontsideratzea behartzen dutenean, planifikazio prozesua aztertu da. Bi prozedura aztertu dira: arazoa zerbitzuen ezaugarrien araberako planifikazio independentetan banatzea edo errestrikzio gogorrenak kontsideratuta, planifikazio bakar bat osatzea. Ikerketaren metodologiari dagokionez, Eragiketen Ikerketako (Winston, Goldberg 2004) zazpi urratsak jarraitu dira: (1) arazoa formulatzea, (2) sistemaren behaketa, (3) arazoaren eredua formulatu, (4) eredua egiaztatzea eta aurreikuspenerako erabiltzea, (5) aukera egokia aukeratzea, (6) azterketaren emaitzak eta ondorioak aurkeztea eta (7) gomendioak ezartzea eta ebaluatzea. Emaitzen arabera, kasu batzuetan ikertu diren bi faktoreek emaitza hobeagoak dakartzatela baieztatu da.A proper crew scheduling impacts on the operational cost of public transport companies. The difficulty of the crew scheduling is due to two main aspects (Esclapés 2001, Bonrostro, Yusta 2003, Ernst et al. 2004, Van den Bergh et al. 2013, Ibarra-Rojas et al. 2015, Li et al. 2015): first, it is part of a larger problem, the Vehicle and Crew Scheduling Problem. Second, the differences among network features, resources of companies, regulatory restrictions or labour agreements make the solutions particular to each company. The main objective of the present research work is “to develop an efficient algorithm which minimizes in an acceptable execution time the Crew Scheduling Problem of an interurban passenger public transport bus company, allowing unlimited drivers’ reliefs that can occur at first, last or any other intermediate stop of a line”. So, using this tool on a real company’s crew scheduling problem, two research gaps found in the analysis of the literature have been examined. On one hand, the impact of allowing unlimited drivers’ reliefs that can occur at first, last or any other intermediate stop of a line. On the other hand, the impact of the scheduling procedure when restrictions vary depending on the type of service that is included in the duty. Two procedures have been studied: dividing the problem into independent problems or scheduling globally under the most limited restrictions. Concerning the research methodology, the seven steps of Operations Research (Winston, Goldberg 2004) have been followed: (1) formulate the problem, (2) observe the system, (3) formulate a model of the problem, (4) verify the model and use the model for prediction, (5) select a suitable alternative, (6) present the results and conclusion of the study and (7) implement and evaluate the recommendations. The results show that occasionally it is worthy to consider both investigated factors

Applications of Genetic Algorithm and Its Variants in Rail Vehicle Systems: A Bibliometric Analysis and Comprehensive Review

Railway systems are time-varying and complex systems with nonlinear behaviors that require effective optimization techniques to achieve optimal performance. Evolutionary algorithms methods have emerged as a popular optimization technique in recent years due to their ability to handle complex, multi-objective issues of such systems. In this context, genetic algorithm (GA) as one of the powerful optimization techniques has been extensively used in the railway sector, and applied to various problems such as scheduling, routing, forecasting, design, maintenance, and allocation. This paper presents a review of the applications of GAs and their variants in the railway domain together with bibliometric analysis. The paper covers highly cited and recent studies that have employed GAs in the railway sector and discuss the challenges and opportunities of using GAs in railway optimization problems. Meanwhile, the most popular hybrid GAs as the combination of GA and other evolutionary algorithms methods such as particle swarm optimization (PSO), ant colony optimization (ACO), neural network (NN), fuzzy-logic control, etc with their dedicated application in the railway domain are discussed too. More than 250 publications are listed and classified to provide a comprehensive analysis and road map for experts and researchers in the field helping them to identify research gaps and opportunities