Results 231 to 240 of about 42,399 (263)
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2014
In the problem session of the ICFCA 2006, Sandor Radeleczki asked for the meaning of the smallest integer k such that a given poset can be decomposed as the union of k directed trees. The problem also asks for the connection of this number to the order dimension.
Sebastian Kerkhoff +1 more
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In the problem session of the ICFCA 2006, Sandor Radeleczki asked for the meaning of the smallest integer k such that a given poset can be decomposed as the union of k directed trees. The problem also asks for the connection of this number to the order dimension.
Sebastian Kerkhoff +1 more
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The decomposition of trees into subtrees
Journal of Graph Theory, 1984AbstractA necessary condition for the decomposition of a tree T into subtrees, each isomorphic to a tree from a given set of trees is presented. We also present a characterization of the set of trees for which the condition is sufficient. Many examples are given.
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2020
In this chapter we review the most important algorithmic approaches to the following problem: given a graph G, compute a tree decomposition of G of (nearly) optimum width. We present the 4-approximation algorithm running in time \(\mathcal {O}(27^k\cdot k^2\cdot n^2)\), which was first proposed by Robertson and Seymour in the Graph Minors series, and ...
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In this chapter we review the most important algorithmic approaches to the following problem: given a graph G, compute a tree decomposition of G of (nearly) optimum width. We present the 4-approximation algorithm running in time \(\mathcal {O}(27^k\cdot k^2\cdot n^2)\), which was first proposed by Robertson and Seymour in the Graph Minors series, and ...
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Decompositions of graphs into trees
Journal of Graph Theory, 1989AbstractLet θ be a family of graphs. By a θ‐decomposition of a graph G we mean a partition λ of the edge set of G such that every F ϵ π spans in G a subgraph isomorphic to a graph in θ.In this paper we state the following conjecture: If T1 and T2 are two trees having relatively prime sizes then there exists c = c(T1 T2) such that every graph G ...
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2008 23rd Annual IEEE Symposium on Logic in Computer Science, 2008
We introduce a notion of definable tree decompositions of graphs. Actually, a definable tree decomposition of a graph is not just a tree decomposition, but a more complicated structure that represents many different tree decompositions of the graph. It is definable in the graph by a tuple of formulas of some logic.
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We introduce a notion of definable tree decompositions of graphs. Actually, a definable tree decomposition of a graph is not just a tree decomposition, but a more complicated structure that represents many different tree decompositions of the graph. It is definable in the graph by a tuple of formulas of some logic.
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Trees and diagrams of decomposition
Studia Logica, 1985A general schema is presented for transformation of and/or proof search trees (in systems with the strong subformula property ensuring termination of the search process) into and-trees. The schema is then generalised to contraction-like rules when a bound of the number of applications in one branch is given.
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Random Structures and Algorithms, 1998
Summary: Let \(H\) be a tree on \(h\geq 2\) vertices. It is shown that if \(G=(V,E)\) is a graph with \(\delta(G)\geq(| V|/2) +10h^4 \sqrt{| V| \log| V|}\), and \(h-1\) divides \(| E|\), then there is a decomposition of the edges of \(G\) into copies of \(H\). This result is asymptotically the best possible for all trees with at least three vertices.
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Summary: Let \(H\) be a tree on \(h\geq 2\) vertices. It is shown that if \(G=(V,E)\) is a graph with \(\delta(G)\geq(| V|/2) +10h^4 \sqrt{| V| \log| V|}\), and \(h-1\) divides \(| E|\), then there is a decomposition of the edges of \(G\) into copies of \(H\). This result is asymptotically the best possible for all trees with at least three vertices.
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Tree Decomposition of Multiclass Problems
2008 10th Brazilian Symposium on Neural Networks, 2008Several popular machine learning techniques are originally designed for the solution of two-class problems. However, several classification problems have more than two classes. One approach to deal with multiclass problems using binary classifiers is to decompose the multiclass problem into multiple binary subproblems disposed in a binary tree.
Ana Carolina Lorena +1 more
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Tree Decomposition with Function Filtering
2005Besides search, complete inference methods can also be used to solve soft constraint problems. Their main drawback is the high spatial complexity. To improve its practical usage, we present an approach to decrease memory consumtion in tree decomposition methods, a class of complete inference algorithms.
Martí Sánchez-Fibla +2 more
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Decomposition Method for Tree Kernels
2007We often meet the tree decomposition task in the tree kernel computing. And tree decomposition tends to vary under different tree mapping constraint. In this paper, we first introduce the general tree decomposition function, and compare the three variants of the function corresponding to different tree mapping.
Peng Huang, Jie Zhu
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