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Semifull Line (Block) Signed Graphs
, 2018 In this paper we introduced the new notions semifull signed graph and semifull line (block) signed graph of a signed graph and its properties are obtained. Also, we obtained the structural characterizations of these notions. Further, we presented some switching equivalent characterizations.
V. Lokesha, P. S. Hemavathi, S. Vijay
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Eigenspaces for \(-2\) in signed line graphs
American Journal of CombinatoricsIt is known that \(-2\) appears in the spectrum of a connected signed line graph if and only if its root is either (a) a balanced signed graph, not a tree, that spans a switching of the complete signed graph or (b) an unbalanced simply signed graph, not a unicyclic simply signed graph, that spans a switching of the signed doubled complete graph.
Zoran Stanić
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Characterizations of line graphs in signed and gain graphs [PDF]
European Journal of Combinatorics, 2022 We generalize three classical characterizations of line graphs to line graphs of signed and gain graphs: the Krausz's characterization, the van Rooij and Wilf's characterization and the Beineke's characterization. In particular, we present a list of forbidden gain subgraphs characterizing the class of gain-line graphs.
Matteo Cavaleri +2 more
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Total graph of a signed graph [PDF]
, 2023 The total graph is built by joining the graph to its line graph by means of the incidences. We introduce a similar construction for signed graphs. Under two similar definitions of the line signed graph, we define the corresponding total signed graph and ...
Stanic Z., Belardo F., Zaslavsky T.
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Star complements for ±2 in signed graphs
Special Matrices, 2022 In this article, we investigate connected signed graphs which have a connected star complement for both −2-2 and 2 (i.e. simultaneously for the two eigenvalues), where −2-2 (resp.
Mulas Raffaella, Stanić Zoran
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Interleaving Automatic Segmentation and Expert Opinion for Retinal Conditions
Diagnostics, 2021 Optical coherence tomography (OCT) has become the leading diagnostic tool in modern ophthalmology. We are interested here in developing a support tool for the segmentation of retina layers. The proposed method relies on graph theory and geodesic distance.
Sergiu Bilc +3 more
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Frontiers in Energy Research, 2021 When nuclear power plants (NPPs) are in a state of failure, they may release radioactive material into the environment. The safety of NPPs must thus be maintained at a high standard. Online monitoring and fault detection and diagnosis (FDD) are important
Wu Guohua +5 more
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Total Minimal Dominating Signed Graph [PDF]
, 2010 Cartwright and Harary considered graphs in which vertices represent persons and the edges represent symmetric dyadic relations amongst persons each of which designated as being positive or negative according to whether the nature of the relationship is ...
Reddy, Siva Kota, Vijay, S.
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On Regular Signed Graphs with Three Eigenvalues
Discussiones Mathematicae Graph Theory, 2020 In this paper our focus is on regular signed graphs with exactly 3 (distinct) eigenvalues. We establish certain basic results; for example, we show that they are walk-regular.
Anđelić Milica +2 more
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, 2009 For standard terminology and notion in graph theory we refer the reader to Harary [7]; the non-standard will be given in this paper as and when required.
Reddy, P. Siva Kota +3 more
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