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Optimal Algorithms for Train Shunting and Relaxed List Update Problems

Tim Nonner, Alexander Souza
unpublished
This problem can also be seen as a relaxed version of the well-known List Update problem, which may be of independent interest.  ...  We derive polynomial time algorithms for Train Shunting by reducing this problem to finding independent sets in bipartite graphs.  ...  We will explain later that we can also think of Train Shunting as a relaxed version of the well-known List Update problem. Contributions.  ... 
fatcat:zai7jfxsirfj7ji4xhz3462egq

Personnel Scheduling on Railway Yards

Roel van den Broek, Han Hoogeveen, Marjan van den Akker, Christos D. Zaroliagis, Dennis Huisman
2020 Algorithmic Approaches for Transportation Modeling, Optimization, and Systems  
This involves an extension of the Train Unit Shunting Problem, in which a conflict-free schedule of all activities at the yard has to be constructed.  ...  These methods are integrated into a local search framework to find feasible solutions to the Train Unit Shunting Problem with staff requirements.  ...  If the reduced cost of the optimal solution to the relaxed pricing problem is non-positive, then the optimal schedule in the original pricing problem is non-positive as well.  ... 
doi:10.4230/oasics.atmos.2020.12 dblp:conf/atmos/BroekH020 fatcat:hqpfssxfbzhf5nkj45z7e5cxpy

Shunting of Passenger Train Units in a Railway Station

Richard Freling, Ramon M. Lentink, Leo G. Kroon, Dennis Huisman
2005 Transportation Science  
Furthermore, a new efficient and speedy solution technique for pricing problems in column generation algorithms is introduced.  ...  In this paper we introduce the problem of shunting passenger train units in a railway station. Shunting occurs whenever train units are temporarily not necessary to operate a given timetable.  ...  The second and third authors were partly sponsored by the Human Potential Program of the European Union under contract no. HPRN-CT-1999-00104 (AMORE).  ... 
doi:10.1287/trsc.1030.0076 fatcat:dqr7zbtdgvclxigsnwzkxr3adu

A Branch-and-Price algorithm for railway rolling stock rescheduling

Richard M. Lusby, Jørgen Thorlund Haahr, Jesper Larsen, David Pisinger
2017 Transportation Research Part B: Methodological  
In this paper we propose a path based mathematical formulation and solve it using a Branch-and-Price algorithm.  ...  How to best reschedule their fleet of rolling stock units during a disruption is an optimization problem regularly faced by railway operators.  ...  Acknowledgements The authors would like to thank the anonymous referees for their valuable comments and the questions that they raised. This feedback has been used to improve the quality of the paper.  ... 
doi:10.1016/j.trb.2017.03.003 fatcat:nma37y4b2fc5zbk23y3aw6ruem

Online Train Shunting

Vianney Boeuf, Frédéric Meunier, Marc Herbstritt
2014 Algorithmic Approaches for Transportation Modeling, Optimization, and Systems  
At the occasion of ATMOS 2012, Tim Nonner and Alexander Souza defined a new train shunting problem that can roughly be described as follows.  ...  We study the online version of the problem, in which cars become known at their source stations. We derive a 2-competitive algorithm and prove than no better ratios are achievable.  ...  Optimal algorithms for train shunting and relaxed list update problems.  ... 
doi:10.4230/oasics.atmos.2014.34 dblp:conf/atmos/BoeufM14 fatcat:m72u4xgg2ncnjdsj3w6ht4egoq

A branch-and-price approach for trip sequence planning of high-speed train units

Yuan Gao, Marie Schmidt, Lixing Yang, Ziyou Gao
2019 Omega : The International Journal of Management Science  
Keywords: Train units scheduling Trip sequence planning Maintenance High-speed railway Branch-and-price algorithm a b s t r a c t In high-speed railway operations, a trip sequence plan is made once the  ...  In light of the maintenance requirements of train units and periodicity characteristics of trip sequences, we introduce a trip sequence graph to describe the train units' movement and coupling/splitting  ...  Acknowledgments We appreciate the editors and the anonymous reviewers for their valuable questions and suggestions.  ... 
doi:10.1016/j.omega.2019.102150 fatcat:3ay7lc5io5bvfiwtaoxbpncvfu

Integrating rolling stock scheduling with train unit shunting

Jørgen Haahr, Richard M. Lusby
2017 European Journal of Operational Research  
Abstract In this paper we consider integrating two important railway optimization problems, in particular the Rolling Stock Scheduling Problem and the Train Unit Shunting Problem.  ...  Highlights • We develop two integrated frameworks for scheduling rolling stock and train unit shunting. • We provide a comparison of several methods for solving the Track Allocation Problem. • We give  ...  In this work we consider integrating two important scheduling problems, in particular the Rolling Stock Scheduling Problem (RSP) and the Train Unit Shunting Problem (TUSP).  ... 
doi:10.1016/j.ejor.2016.10.053 fatcat:m4dxyg4nwzdr7dlysmeu6zxhv4

A Decomposition Algorithm for Large-Scale Security-Constrained AC Optimal Power Flow [article]

Frank E. Curtis, Daniel K. Molzahn, Shenyinying Tu, Andreas Wächter, Ermin Wei, Elizabeth Wong
2021 arXiv   pre-print
A decomposition algorithm for solving large-scale security-constrained AC optimal power flow problems is presented.  ...  , avoiding issues related to degeneracy, and exploiting parallelism.  ...  Acknowledgment The authors would like to acknowledge Xingyi He for the training of the machine learning model for the initial ranking of contingencies.  ... 
arXiv:2110.01737v1 fatcat:6v3a73ivuzhvtpgybs7fgaw27q

A Comparison of Two Exact Methods for Passenger Railway Rolling Stock (Re)Scheduling

J orgen T. Haahr, Joris Wagenaar, Lucas P. Veelenturf, Leo G. Kroon
2015 Social Science Research Network  
For the rescheduling instances, the original rolling stock schedule, an updated timetable, and the passenger demand are given.  ...  When no columns exist with negative reduced cost we have solved the LP relaxation to optimality.  ... 
doi:10.2139/ssrn.2624679 fatcat:aaoqoroxbbfe5cf4ogtbopr66i

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

Jørgen T. Haahr, Joris C. Wagenaar, Lucas P. Veelenturf, Leo G. Kroon
2016 Transportation Research Part E: Logistics and Transportation Review  
For the rescheduling instances, the original rolling stock schedule, an updated timetable, and the passenger demand are given.  ...  When no columns exist with negative reduced cost we have solved the LP relaxation to optimality.  ... 
doi:10.1016/j.tre.2016.03.019 fatcat:meaidj4j65bnpallckwqpzdudm

Generation of Dynamically Configured Check Lists for Intra-Operative Problems: Using a Set Covering Algorithm

T. Sawa
2002 JAMIA Journal of the American Medical Informatics Association  
A neural network approach for seeking optimal disease sets was given by Cho and Reggia. 11 Vinterbo and Ohno-Machado 8 reported a genetic algorithm approach for searching optimal disease sets.  ...  Set Covering Theory and Reggia's Algorithm Set covering theory has been previously applied in medicine in search for optimal sets of diseases given a set of symptoms.  ... 
doi:10.1197/jamia.m1221 fatcat:r5k6owrtoreq5hm2zuufpzhoka

An Empirical Study on the Comprehensive Optimization Method of a Train Diagram of the China High Speed Railway Express

Xueqiao Yu, Maoxiang Lang, Wenhui Zhang, Shiqi Li, Mingyue Zhang, Xiao Yu
2019 Sustainability  
algorithm based on the Lagrange relaxation algorithm is designed.  ...  The rapid and stable development of China's economy has driven the increasing demand for express transportation.  ...  For this kind of problem, the Lagrange relaxation algorithm has a good solution effect.  ... 
doi:10.3390/su11072141 fatcat:3ggq6hqctraa3ej4usgnddhlqq

HydroPowerModels.jl: A Julia/JuMP Package for Hydrothermal Economic Dispatch Optimization

2020 JuliaCon Proceedings  
We use JuMP, a package for mathematical programming modeling; PowerModels.jl, a JuMP-extension for power network optimization; and SDDP.jl, another extension that implements the SDDP algorithm.  ...  HydroPowerModels.jl is a Julia package for solving multistage, steady-state, hydro-dominated, power network optimization problems with stochastic dual dynamic programming (SDDP).  ...  Different convex relaxations were proposed for the optimal power flow problem, here we highlight some of the most important ones.  ... 
doi:10.21105/jcon.00035 fatcat:zzn2emtyh5g6befleigbol57hi

A branch-and-price approach for solving the train unit scheduling problem

Zhiyuan Lin, Raymond S.K. Kwan
2016 Transportation Research Part B: Methodological  
We propose a branch-and-price approach for solving the integer multicommodity flow model for the network-level train unit scheduling problem (TUSP).  ...  The branch-and-price solver designed for TUSP is capable of handling instances of up to about 500 train trips.  ...  We would like to also thank First ScotRail and Southern Railway for their kind and helpful collaboration.  ... 
doi:10.1016/j.trb.2016.09.007 fatcat:sgwcjapac5elzfrinp2rtwolc4

An overview of recovery models and algorithms for real-time railway rescheduling

Valentina Cacchiani, Dennis Huisman, Martin Kidd, Leo Kroon, Paolo Toth, Lucas Veelenturf, Joris Wagenaar
2014 Transportation Research Part B: Methodological  
This paper presents an overview of recovery models and algorithms for real-time railway disturbance and disruption management.  ...  The application of these models and algorithms in real-life railway systems will be instrumental for increasing the quality of the provided railway services, leading to an increased utilization of the  ...  The branch-and-bound algorithm is able to obtain the optimal solution for 297 out of 300 instances.  ... 
doi:10.1016/j.trb.2014.01.009 fatcat:5flkhivktjgjfi37jdyo3wdmsy
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