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Related papers: Single-Source Unsplittable Flows in Planar Graphs

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The classical Okamura-Seymour theorem states that for an edge-capacitated, multi-commodity flow instance in which all terminals lie on a single face of a planar graph, there exists a feasible concurrent flow if and only if the cut…

Combinatorics · Mathematics 2015-06-18 James R. Lee , Manor Mendel , Mohammad Moharrami

Utilizing graph algorithms is a common activity in computer science. Algorithms that perform computations on large graphs are not always efficient. This work investigates the Single-Source Shortest Path (SSSP) problem, which is considered…

Data Structures and Algorithms · Computer Science 2021-06-25 Ahmed Shokry

The robust minimum cost flow problem under consistent flow constraints (RobMCF$\equiv$) is a new extension of the minimum cost flow (MCF) problem. In the RobMCF$\equiv$ problem, we consider demand and supply that are subject to uncertainty.…

Optimization and Control · Mathematics 2020-08-06 Christina Büsing , Arie M. C. A. Koster , Sabrina Schmitz

We consider bifurcation of solutions from a given trivial branch for a class of strongly indefinite elliptic systems via the spectral flow. Our main results establish bifurcation invariants that can be obtained from the coefficients of the…

Analysis of PDEs · Mathematics 2015-12-15 Nils Waterstraat

We study an entropic optimal transport problem in which the transport plan is penalized by a nonlinear convex functional acting on the coupling. We establish existence, uniqueness, and uniform a priori bounds for minimizers, and we show…

Optimization and Control · Mathematics 2025-12-15 Anna Kazeykina , Zhenjie Ren , Xiaozhen Wang , Yufei Zhang

In this paper, we study fractional multiflows in undirected graphs. A fractional multiflow in a graph G with a node subset T, called terminals, is a collection of weighted paths with ends in T such that the total weights of paths traversing…

Discrete Mathematics · Computer Science 2011-06-03 N. Vanetik

Minimum cuts have been closely related to shortest paths in planar graphs via planar duality - so long as the graphs are undirected. Even maximum flows are closely related to shortest paths for the same reason - so long as the source and…

Data Structures and Algorithms · Computer Science 2013-05-27 Glencora Borradaile , Anna Harutyunyan

We present the derivation of a new unidirectional model for We present the derivation of a new unidirectional model for unsteady mixed flows in non uniform closed water pipes. We introduce a local reference frame to take into account the…

Analysis of PDEs · Mathematics 2010-06-02 Christian Bourdarias , Mehmet Ersoy , Stéphane Gerbi

Millions of flows are routed concurrently through a modern data-center. These networks are often built as Clos topologies, and flow demands are constrained only by the link capacities at the ingress and egress points. The minimum congestion…

Networking and Internet Architecture · Computer Science 2025-05-08 Miguel Ferreira , Nirav Atre , Justine Sherry , Michael Dinitz , João Luís Sobrinho

The construction of a cost minimal network for flows obeying physical laws is an important problem for the design of electricity, water, hydrogen, and natural gas infrastructures. We formulate this problem as a mixed-integer non-linear…

Optimization and Control · Mathematics 2025-03-31 Pascal Börner , Max Klimm , Annette Lutz , Marc E. Pfetsch , Martin Skutella , Lea Strubberg

We consider network models where information items flow %are sent from a source to a sink node. We start with a model where routing is constrained by energy available on nodes in finite supply (like in Smartdust) and efficiency is related…

Discrete Mathematics · Computer Science 2024-05-24 Pietro Cenciarelli , Daniele Gorla , Ivano Salvo

We consider a general stable flow problem in a directed and capacitated network, where each vertex has a strict preference list over the incoming and outgoing edges. A flow is stable if no group of vertices forming a path can mutually…

Computer Science and Game Theory · Computer Science 2020-08-11 Young-San Lin , Thanh Nguyen

In this work, we develop a new framework for dynamic network flow problems based on optimal transport theory. We show that the dynamic multi-commodity minimum-cost network flow problem can be formulated as a multi-marginal optimal transport…

Optimization and Control · Mathematics 2021-06-29 Isabel Haasler , Axel Ringh , Yongxin Chen , Johan Karlsson

We introduce a new approach to computing an approximately maximum s-t flow in a capacitated, undirected graph. This flow is computed by solving a sequence of electrical flow problems. Each electrical flow is given by the solution of a…

Data Structures and Algorithms · Computer Science 2010-10-20 Paul Christiano , Jonathan A. Kelner , Aleksander Madry , Daniel A. Spielman , Shang-Hua Teng

The relationship between the sparsest cut and the maximum concurrent multi-flow in graphs has been studied extensively. For general graphs with $k$ terminal pairs, the flow-cut gap is $O(\log k)$, and this is tight. But when topological…

Data Structures and Algorithms · Computer Science 2018-11-08 Robert Krauthgamer , James R. Lee , Havana Rika

The maximum integer skew-symmetric flow problem (MSFP) generalizes both the maximum flow and maximum matching problems. It was introduced by Tutte in terms of self-conjugate flows in antisymmetrical digraphs. He showed that for these…

Combinatorics · Mathematics 2010-11-15 Andrew V. Goldberg , Alexander V. Karzanov

Given a directed graph and a source vertex, the fully dynamic single-source reachability problem is to maintain the set of vertices that are reachable from the given vertex, subject to edge deletions and insertions. It is one of the most…

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

We study the flow spectrum ${\cal S}(G)$ and the integer flow spectrum $\overline{{\cal S}}(G)$ of signed $(2t+1)$-regular graphs. We show that if $r \in {\cal S}(G)$, then $r = 2+\frac{1}{t}$ or $r \geq 2 + \frac{2}{2t-1}$. Furthermore, $2…

Combinatorics · Mathematics 2015-09-22 Michael Schubert , Eckhard Steffen

The theory of graph limits is only understood to any nontrivial degree in the cases of dense graphs and of bounded degree graphs. There is, however, a lot of interest in the intermediate cases. It appears that the most important…

Combinatorics · Mathematics 2021-02-17 Laszlo Lovasz

The multi-commodity flow-cut gap is a fundamental parameter that affects the performance of several divide \& conquer algorithms, and has been extensively studied for various classes of undirected graphs. It has been shown by Linial, London…

Data Structures and Algorithms · Computer Science 2017-11-07 Ario Salmasi , Anastasios Sidiropoulos , Vijay Sridhar