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Related papers: Exploration of Periodically Varying Graphs

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A temporal graph is a graph in which the edge set can change from one time step to the next. The temporal graph exploration problem TEXP is the problem of computing a foremost exploration schedule for a temporal graph, i.e., a temporal walk…

Data Structures and Algorithms · Computer Science 2021-03-17 Thomas Erlebach , Michael Hoffmann , Frank Kammer

We investigate the computational complexity of finding temporally disjoint paths or walks in temporal graphs. There, the edge set changes over discrete time steps and a temporal path (resp. walk) uses edges that appear at monotonically…

Data Structures and Algorithms · Computer Science 2021-05-25 Nina Klobas , George B. Mertzios , Hendrik Molter , Rolf Niedermeier , Philipp Zschoche

Most transportation networks are inherently temporal: Connections (e.g. flights, train runs) are only available at certain, scheduled times. When transporting passengers or commodities, this fact must be considered for the the planning of…

Data Structures and Algorithms · Computer Science 2022-01-17 Eugen Füchsle , Hendrik Molter , Rolf Niedermeier , Malte Renken

In this paper we initiate the study of the temporal graph realization problem with respect to the fastest path durations among its vertices, while we focus on periodic temporal graphs. Given an $n \times n$ matrix $D$ and a $\Delta \in…

Data Structures and Algorithms · Computer Science 2024-05-02 Nina Klobas , George B. Mertzios , Hendrik Molter , Paul G. Spirakis

We give unconditional parameterized complexity lower bounds on pure dynamic programming algorithms - as modeled by tropical circuits - for connectivity problems such as the Traveling Salesperson Problem. Our lower bounds are higher than the…

Computational Complexity · Computer Science 2025-12-30 Kacper Kluk , Jesper Nederlof

The fully dynamic transitive closure problem asks to maintain reachability information in a directed graph between arbitrary pairs of vertices, while the graph undergoes a sequence of edge insertions and deletions. The problem has been…

Data Structures and Algorithms · Computer Science 2020-02-04 Kathrin Hanauer , Monika Henzinger , Christian Schulz

In robotic planetary surface exploration, strategic mobility planning is an important task that involves finding candidate long-distance routes on orbital maps and identifying segments with uncertain traversability. Then, expert human…

Robotics · Computer Science 2026-05-08 Olivier Lamarre , Jonathan Kelly

Graph exploration is one of the fundamental tasks performed by a mobile agent in a graph. An $n$-node graph has unlabeled nodes, and all ports at any node of degree $d$ are arbitrarily numbered $0,\dots, d-1$. A mobile agent, initially…

Data Structures and Algorithms · Computer Science 2023-03-21 Andrzej Pelc

In this paper we study the fixed-parameter tractability of the problem of deciding whether a given temporal graph admits a temporal walk that visits all vertices (temporal exploration) or, in some problem variants, a certain subset of the…

Data Structures and Algorithms · Computer Science 2022-12-06 Thomas Erlebach , Jakob T. Spooner

Time-evolving or temporal graphs gain more and more popularity when studying the behavior of complex networks. In this context, the multistage view on computational problems is among the most natural frameworks. Roughly speaking, herein one…

Computational Complexity · Computer Science 2020-07-30 Klaus Heeger , Anne-Sophie Himmel , Frank Kammer , Rolf Niedermeier , Malte Renken , Andrej Sajenko

We initiate the study of the parameterized complexity of the {\sc Collective Graph Exploration} ({\sc CGE}) problem. In {\sc CGE}, the input consists of an undirected connected graph $G$ and a collection of $k$ robots, initially placed at…

Data Structures and Algorithms · Computer Science 2023-10-10 Siddharth Gupta , Guy Sa'ar , Meirav Zehavi

The problem Orienteering asks whether there exists a walk which visits a number of sites without exceeding some fuel budget. In the variant of the problem we consider, the cost of each edge in the walk is dependent on the time we depart one…

Discrete Mathematics · Computer Science 2025-07-02 Timothée Corsini , Jessica Enright , Laura Larios-Jones , Kitty Meeks

We study the complexity of the directed periodic temporal graph realization problem. This work is motivated by the design of periodic schedules in public transport with constraints on the quality of service. Namely, we require that the…

Data Structures and Algorithms · Computer Science 2025-09-15 Julia Meusel , Matthias Müller-Hannemann , Klaus Reinhardt

We consider the problem of collective exploration of a known $n$-node edge-weighted graph by $k$ mobile agents that have limited energy but are capable of energy transfers. The agents are initially placed at an arbitrary subset of nodes in…

Discrete Mathematics · Computer Science 2021-02-26 J. Czyzowicz , S. Dobrev , R. Killick , E. Kranakis , D. Krizanc , L. Narayanan , J. Opatrny , D. Pankratov , S. Shende

The $n$-vehicle exploration problem (NVEP) is a nonlinear unconstrained optimization problem. Given a fleet of $n$ vehicles with mid-trip refueling technique, the NVEP tries to find a sequence of $n$ vehicles to make one of the vehicles…

Computational Complexity · Computer Science 2024-09-17 Jinchuan Cui , Xiaoya Li

In a temporal graph, each edge is available at specific points in time. Such an availability point is often represented by a ''temporal edge'' that can be traversed from its tail only at a specific departure time, for arriving in its head…

Data Structures and Algorithms · Computer Science 2023-01-31 Filippo Brunelli , Laurent Viennot

We study the design of small cost temporally connected graphs, under various constraints. We mainly consider undirected graphs of $n$ vertices, where each edge has an associated set of discrete availability instances (labels). A journey…

Discrete Mathematics · Computer Science 2016-07-07 Eleni C. Akrida , Leszek Gasieniec , George B. Mertzios , Paul G. Spirakis

Planning for Autonomous Unmanned Ground Vehicles (AUGV) is still a challenge, especially in difficult, off-road, critical situations. Automatic planning can be used to reach mission objectives, to perform navigation or maneuvers. Most of…

Artificial Intelligence · Computer Science 2021-08-03 Kevin Osanlou , Christophe Guettier , Andrei Bursuc , Tristan Cazenave , Eric Jacopin

Temporal graphs are graphs with time-stamped edges. We study the problem of finding a small vertex set (the separator) with respect to two designated terminal vertices such that the removal of the set eliminates all temporal paths…

Data Structures and Algorithms · Computer Science 2018-07-26 Philipp Zschoche , Till Fluschnik , Hendrik Molter , Rolf Niedermeier

We investigate the computational complexity of separating two distinct vertices s and z by vertex deletion in a temporal graph. In a temporal graph, the vertex set is fixed but the edges have (discrete) time labels. Since the corresponding…

Computational Complexity · Computer Science 2020-10-12 Till Fluschnik , Hendrik Molter , Rolf Niedermeier , Malte Renken , Philipp Zschoche