2 Search Results for "Veelenturf, Lucas P."

Document
DOI: 10.4230/LIPIcs.SAND.2025.7
Better Late, Then? The Hardness of Choosing Delays to Meet Passenger Demands in Temporal Graphs

Authors: David C. Kutner and Anouk Sommer

Published in: LIPIcs, Volume 330, 4th Symposium on Algorithmic Foundations of Dynamic Networks (SAND 2025)

Abstract
In train networks, carefully-chosen delays may be beneficial for certain passengers, who would otherwise miss some connection. Given a simple (directed or undirected) temporal graph and a set of passengers (each specifying a starting vertex, an ending vertex, and a desired arrival time), we ask whether it is possible to delay some of the edges of the temporal graph to realize all the passengers' demands. We call this problem DelayBetter (DB), and study it along with two variants: in δ-DelayBetter, each delay must be of at most δ; in (δ-)Path DB, passengers also fully specify the vertices they should visit on their journey. On the positive side, we give a polynomial-time algorithm for Path DB and δ-Path DB, and obtain as a corollary a polynomial-time algorithm for DB and δ-DB on trees. We also provide an fpt algorithm for both problems parameterized by the size of the graph’s Feedback Edge Set together with the number of passengers. On the negative side, we show NP-completeness of (1-)DB on bounded-degree temporal graphs even when the lifetime is 2, and of (10-)DB on bounded-degree planar temporal graphs of lifetime 19. Our results complement previous work studying reachability problems in temporal graphs with delaying operations. This is to our knowledge the first such problem in which the aim is to facilitate travel between specific points (as opposed to facilitating or impeding a broadcast from one or many sources).
Cite as

David C. Kutner and Anouk Sommer. Better Late, Then? The Hardness of Choosing Delays to Meet Passenger Demands in Temporal Graphs. In 4th Symposium on Algorithmic Foundations of Dynamic Networks (SAND 2025). Leibniz International Proceedings in Informatics (LIPIcs), Volume 330, pp. 7:1-7:18, Schloss Dagstuhl – Leibniz-Zentrum für Informatik (2025)

Copy BibTex To Clipboard

@InProceedings{kutner_et_al:LIPIcs.SAND.2025.7,
  author =	{Kutner, David C. and Sommer, Anouk},
  title =	{{Better Late, Then? The Hardness of Choosing Delays to Meet Passenger Demands in Temporal Graphs}},
  booktitle =	{4th Symposium on Algorithmic Foundations of Dynamic Networks (SAND 2025)},
  pages =	{7:1--7:18},
  series =	{Leibniz International Proceedings in Informatics (LIPIcs)},
  ISBN =	{978-3-95977-368-3},
  ISSN =	{1868-8969},
  year =	{2025},
  volume =	{330},
  editor =	{Meeks, Kitty and Scheideler, Christian},
  publisher =	{Schloss Dagstuhl -- Leibniz-Zentrum f{\"u}r Informatik},
  address =	{Dagstuhl, Germany},
  URL =		{https://drops.dagstuhl.de/entities/document/10.4230/LIPIcs.SAND.2025.7},
  URN =		{urn:nbn:de:0030-drops-230604},
  doi =		{10.4230/LIPIcs.SAND.2025.7},
  annote =	{Keywords: Temporal Graphs, Computational Complexity, Delay Management, Train Networks}
}
Document
DOI: 10.4230/OASIcs.ATMOS.2023.8
Fewer Trains for Better Timetables: The Price of Fixed Line Frequencies in the Passenger-Oriented Timetabling Problem

Authors: Pedro José Correia Duarte, Marie Schmidt, Dennis Huisman, and Lucas P. Veelenturf

Published in: OASIcs, Volume 115, 23rd Symposium on Algorithmic Approaches for Transportation Modelling, Optimization, and Systems (ATMOS 2023)

Abstract
This paper introduces the Passenger-Oriented Timetabling problem with flexible frequencies (POT-flex) in the context of railway planning problems. POT-flex aims at creating feasible railway timetables minimising total perceived passenger travel time. The contribution of the POT-flex lies in its relaxation of the generally adopted assumption that line frequencies should be a fixed part of the input. Instead, we consider flexible line frequencies, encompassing a minimum and maximum frequency per line, allowing the timetabling model to decide on optimal line frequencies to obtain better solutions using fewer train services per line. We develop a mixed-integer programming formulation for POT-flex based on the Passenger-Oriented Timetabling (POT) formulation of [Polinder et al., 2021] and compare the performance of the new formulation against the POT formulation on three instances. We find that POT-flex allows to find feasible timetables in instances containing bottlenecks, and show improvements of up to 2% on the largest instance tested. These improvements highlight the cost that fixed line frequencies can have on timetabling.
Cite as

Pedro José Correia Duarte, Marie Schmidt, Dennis Huisman, and Lucas P. Veelenturf. Fewer Trains for Better Timetables: The Price of Fixed Line Frequencies in the Passenger-Oriented Timetabling Problem. In 23rd Symposium on Algorithmic Approaches for Transportation Modelling, Optimization, and Systems (ATMOS 2023). Open Access Series in Informatics (OASIcs), Volume 115, pp. 8:1-8:18, Schloss Dagstuhl – Leibniz-Zentrum für Informatik (2023)

Copy BibTex To Clipboard

@InProceedings{correiaduarte_et_al:OASIcs.ATMOS.2023.8,
  author =	{Correia Duarte, Pedro Jos\'{e} and Schmidt, Marie and Huisman, Dennis and Veelenturf, Lucas P.},
  title =	{{Fewer Trains for Better Timetables: The Price of Fixed Line Frequencies in the Passenger-Oriented Timetabling Problem}},
  booktitle =	{23rd Symposium on Algorithmic Approaches for Transportation Modelling, Optimization, and Systems (ATMOS 2023)},
  pages =	{8:1--8:18},
  series =	{Open Access Series in Informatics (OASIcs)},
  ISBN =	{978-3-95977-302-7},
  ISSN =	{2190-6807},
  year =	{2023},
  volume =	{115},
  editor =	{Frigioni, Daniele and Schiewe, Philine},
  publisher =	{Schloss Dagstuhl -- Leibniz-Zentrum f{\"u}r Informatik},
  address =	{Dagstuhl, Germany},
  URL =		{https://drops.dagstuhl.de/entities/document/10.4230/OASIcs.ATMOS.2023.8},
  URN =		{urn:nbn:de:0030-drops-187695},
  doi =		{10.4230/OASIcs.ATMOS.2023.8},
  annote =	{Keywords: PESP, Passenger Oriented Timetabling, Perceived Travel Time}
}
  • Refine by Type
  • 2 Document/PDF
  • 1 Document/HTML

  • Refine by Publication Year
  • 1 2025
  • 1 2023

  • Refine by Author
  • 1 Correia Duarte, Pedro José
  • 1 Huisman, Dennis
  • 1 Kutner, David C.
  • 1 Schmidt, Marie
  • 1 Sommer, Anouk
  • Show More...

  • Refine by Series/Journal
  • 1 LIPIcs
  • 1 OASIcs

  • Refine by Classification
  • 1 Applied computing → Transportation
  • 1 Mathematics of computing → Graph theory
  • 1 Theory of computation → Computational complexity and cryptography

  • Refine by Keyword
  • 1 Computational Complexity
  • 1 Delay Management
  • 1 PESP
  • 1 Passenger Oriented Timetabling
  • 1 Perceived Travel Time
  • Show More...

Any Issues?
X

Feedback on the Current Page

CAPTCHA

Thanks for your feedback!

Feedback submitted to Dagstuhl Publishing

Could not send message

Please try again later or send an E-mail
© 2023-2026 Schloss Dagstuhl – LZI GmbH Schloss Dagstuhl – LZI GmbH About DROPS Imprint Privacy Contact