Results 11 to 20 of about 34,755 (248)
Characterization of line-consistent signed graphs [PDF]
Discussiones Mathematicae Graph Theory, 2015 5 pages. V2 defines sign of a walk and corrects statement of Theorem 4 ("is balanced and" was missing); also minor ...
Daniel C. Slilaty, Thomas Zaslavsky
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Signed analogue of line graphs and their smallest eigenvalues [PDF]
Journal of Graph Theory, 2021 AbstractIn this article, we show that every connected signed graph with smallest eigenvalue strictly greater than and large enough minimum degree is switching equivalent to a complete graph. This is a signed analogue of a theorem of Hoffman. The proof is based on what we call Hoffman's limit theorem which we formulate for Hermitian matrices, and also ...
Alexander L Gavrilyuk +2 more
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On •-line signed graphs L_{•}(S)
Discussiones Mathematicae Graph Theory, 2015 A signed graph (or sigraph for short) is an ordered pair S = (Su,σ), where Su is a graph, G = (V,E), called the underlying graph of S and σ : E → {+,−} is a function from the edge set E of Su into the set {+,−}. For a sigraph S its •-line sigraph, L•(S) is the sigraph in which the edges of S are represented as vertices, two of these vertices are ...
Sinha Deepa, Dhama Ayushi
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Line Signed Graph of a Signed Total Graph
Electronic Notes in Discrete Mathematics, 2017 Abstract A signed total graph is an ordered pair T Σ ( Γ ( R ) ) : = ( T ( Γ ( R ) ) , σ ) , where T ( Γ ( R ) ) is the total graph of a commutative ring R, called the underlying graph of T Σ ( Γ ( R ) ) and T Σ ( Γ ( R ) ) is associated with a signing of its edges (a, b)
Mukti Acharya, Atul Gaur
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Consistency in the Naturally Vertex-Signed Line Graph of a Signed Graph [PDF]
Bulletin of the Malaysian Mathematical Sciences Society, 2015 A signed graph is a graph whose edges are signed. In a vertex-signed graph the vertices are signed. The latter is called consistent if the product of signs in every circle is positive. The line graph of a signed graph is naturally vertex-signed. Based on a characterization by Acharya, Acharya, and Sinha in 2009, we give constructions for the signed ...
Thomas Zaslavsky, Zaslavsky Thomas
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The H-Line Signed Graph Of A Signed Graph [PDF]
, 2010 For standard terminology and notion in graph theory we refer the reader to Harary; the non-standard will be given in this paper as and when required. We treat only finite simple graphs without self loops and isolates.
Rangarajan, R. +2 more
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Signed graphs connected with the root lattice
Bibechana, 2014 For any base of the root lattice (An) we can construct a signed graph. A signed graph is one whose edges are signed by +1 or -1. A signed graph is balanced if and only if its vertex set can be divided into two sets-either of which may be empty–so that ...
RN Yadav
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Characterization of Line-Cut Signed Graphs
The National Academy of Sciences, India, 2020 A signed graph $$S=(S^u,\sigma )$$ consists of an underlying graph $$S^u$$ and a function ...
Sangita Kansal
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Line and Subdivision Graphs Determined by
Mathematics, 2019 Let T 4 = { ± 1 , ± i } be the subgroup of fourth roots of unity inside T , the multiplicative group of complex units. For a T 4 -gain graph Φ = ( Γ , T 4 , φ ) , we introduce gain functions on ...
Abdullah Alazemi +4 more
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On-line fault diagnosis using the signed directed graph [PDF]
Industrial & Engineering Chemistry Research, 1990 Fault diagnosis using structural knowledge, namely, the signed directed graph (SDG), is presented. A design procedure is proposed to overcome several problems associated with the SDG : it produces spurious (multiple) interpretations and it may delete the true interpretation when the process variable is going through nonsingle transition (this is ...
Chang, Chung Chien, Yu, Cheng Ching
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