Results 31 to 40 of about 275 (182)
Factorization theorems for strong maps between matroids of arbitrary cardinality
Open Mathematics, 2016 In this paper we present factorization theorems for strong maps between matroids of arbitrary cardinality. Moreover, we present a new way to prove the factorization theorem for strong maps between finite matroids.
Mao Hua
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A Note on Ultrametric Spaces, Minimum Spanning Trees and the Topological Distance Algorithm
Information, 2020 We relate the definition of an ultrametric space to the topological distance algorithm—an algorithm defined in the context of peer-to-peer network applications.
Jörg Schäfer
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Invariants of vector configurations [PDF]
Discrete Mathematics & Theoretical Computer Science, 2012 We investigate the Zariski closure of the projective equivalence class of a matrix. New results are presented regarding the matrices in this variety and their matroids, and we give equations for the variety.
Andrew Berget, Alex Fink
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Matroids on the Bases of Simple Matroids
European Journal of Combinatorics, 1981 Let M be a simple matroid (= combinatorial geometry). On the bases of M we consider two matroids S(M, F) and H(M, F), which depend on a field F. S(M, F) is the simplicial matroid with coefficients in F on the bases of M considered as simplices. H(M, F) has been studied by Björner in [1].
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A characterization of the base-matroids of a graphic matroid
Contributions to Discrete Mathematics, 2010 Let M=(E,F) be a matroid on a set E and B one of its bases. A closed set θ⊆E is saturated with respect to B when |θ∩B|≤r(θ), where r(θ) is the rank of θ. The collection of subsets I of E such that |I∩θ|≤r(θ) for every closed saturated set θ turns out to be the family of independent sets of a new matroid on E, called base-matroid and denoted by MB.
MAFFIOLI, FRANCESCO, ZAGAGLIA, NORMA
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Combinatorics of Positroids [PDF]
Discrete Mathematics & Theoretical Computer Science, 2009 Recently Postnikov gave a combinatorial description of the cells in a totally-nonnegative Grassmannian. These cells correspond to a special class of matroids called positroids.
Suho Oh
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Edge‐Length Preserving Embeddings of Graphs Between Normed Spaces
Journal of Graph Theory, Volume 112, Issue 4, Page 491-506, August 2026.ABSTRACT The concept of graph embeddability, initially formalized by Belk and Connelly and later expanded by Sitharam and Willoughby, extends the question of embedding finite metric spaces into a given normed space. A finite simple graph G = ( V , E ) is said to be ( X , Y )‐embeddable if any set of induced edge lengths from an embedding of G into a ...
Sean Dewar +3 more
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Matroidal Structure of Rough Sets from the Viewpoint of Graph Theory
Journal of Applied Mathematics, 2012 Constructing structures with other mathematical theories is an important research field of rough sets. As one mathematical theory on sets, matroids possess a sophisticated structure.
Jianguo Tang, Kun She, William Zhu
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When is the graph of a random 0/1 polytope a clique?
Bulletin of the London Mathematical Society, Volume 58, Issue 8, August 2026.Abstract We study graph‐theoretic properties of random 0/1$0/1$ polytopes. Specifically, let Qpn⊆{0,1}n$Q_p^n \subseteq \lbrace 0,1\rbrace ^n$ be a random subset where each point is included independently with probability p$p$, and consider the graph Gp$G_p$ of the polytope conv(Qpn)$\operatorname{conv}(Q_p^n)$.
Catherine Babecki +2 more
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Applications of Matrices to a Matroidal Structure of Rough Sets
Journal of Applied Mathematics, 2013 Rough sets provide an efficient tool for dealing with the vagueness and granularity in information systems. They are widely used in attribute reduction in data mining. There are many optimization issues in attribute reduction.
Jingqian Wang, William Zhu
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