Results 91 to 100 of about 13,679 (262)
On Low Treewidth Graphs and Supertrees [PDF]
Compatibility of unrooted phylogenetic trees is a well studied problem in phylogenetics. It asks to determine whether for a set of k input trees T1,...,Tk there exists a larger tree (called a supertree) that contains the topologies of all k input trees. When any such supertree exists we call the instance compatible and otherwise incompatible.
Alexander Grigoriev+2 more
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Fast Diameter Computation within Split Graphs [PDF]
When can we compute the diameter of a graph in quasi linear time? We address this question for the class of {\em split graphs}, that we observe to be the hardest instances for deciding whether the diameter is at most two.
Guillaume Ducoffe+2 more
doaj +1 more source
Kernel Bounds for Structural Parameterizations of Pathwidth [PDF]
Assuming the AND-distillation conjecture, the Pathwidth problem of determining whether a given graph G has pathwidth at most k admits no polynomial kernelization with respect to k.
B. Monien+14 more
core +1 more source
The treewidth of a graph is an important invariant in structural and algorithmic graph theory. This paper studies the treewidth of line graphs. We show that determining the treewidth of the line graph of a graph $G$ is equivalent to determining the minimum vertex congestion of an embedding of $G$ into a tree.
Daniel J. Harvey, David R. Wood
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Knot Diagrams of Treewidth Two [PDF]
In this paper, we study knot diagrams for which the underlying graph has treewidth two. We give a linear time algorithm for the following problem: given a knot diagram of treewidth two, does it represent the unknot? We also show that for a link diagram of treewidth two we can test in linear time if it represents the unlink.
Bodlaender, Hans L.+3 more
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The Treewidth of Java Programs
Intuitively, the treewidth of a graph $G$ measures how close $G$ is to being a tree. The lower the treewidth, the faster we can solve various optimization problems on $G$, by dynamic programming along the tree structure. In the paper M.Thorup, All Structured |Programs have Small Tree-Width and Good Register Allocation [8] it is shown that the control ...
Gustedt, Jens+2 more
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Intersection Dimension and Graph Invariants
We show that the intersection dimension of graphs with respect to several hereditary properties can be bounded as a function of the maximum degree. As an interesting special case, we show that the circular dimension of a graph with maximum degree Δ is at
Aravind N.R., Subramanian C.R.
doaj +1 more source
Tractable Inference for Hybrid Bayesian Networks with NAT-Modeled Dynamic Discretization
Hybrid BNs (HBNs) extend Bayesian networks (BNs) to both discrete and continuous variables. Among inference methods for HBNs, we focus on dynamic discretization (DD) that converts HBN to discrete BN for inference.
Yang Xiang, Hanwen Zheng
doaj +1 more source
First-order queries on classes of structures with bounded expansion [PDF]
We consider the evaluation of first-order queries over classes of databases with bounded expansion. The notion of bounded expansion is fairly broad and generalizes bounded degree, bounded treewidth and exclusion of at least one minor.
Wojtek Kazana, Luc Segoufin
doaj +1 more source
Treewidth and pathwidth of permutation graphs [PDF]
In this paper we show that the treewidth and pathwidth of a permutation graph can be computed in polynomial time. In fact we show that, for permutation graphs, the treewidth and pathwidth are equal. These results make permutation graphs one of the few non-trivial graph classes for which at the moment, treewidth is known to be computable in polynomial ...
Ton Kloks+2 more
openaire +4 more sources