Results 21 to 30 of about 184,542 (302)

Incidence matrices and line graphs of mixed graphs

open access: yesSpecial Matrices, 2023
In the theory of line graphs of undirected graphs, there exists an important theorem linking the incidence matrix of the root graph to the adjacency matrix of its line graph. For directed or mixed graphs, however, there exists no analogous result.
Abudayah Mohammad   +2 more
doaj   +1 more source

Markov properties for mixed graphs [PDF]

open access: yesBernoulli, 2014
In this paper, we unify the Markov theory of a variety of different types of graphs used in graphical Markov models by introducing the class of loopless mixed graphs, and show that all independence models induced by $m$-separation on such graphs are compositional graphoids.
Sadeghi, Kayvan, Lauritzen, Steffen
openaire   +5 more sources

Mixed metric dimension of graphs [PDF]

open access: yesApplied Mathematics and Computation, 2017
arXiv admin note: text overlap with arXiv:1602 ...
Aleksander Kelenc   +3 more
openaire   +4 more sources

The Vertex-Edge Resolvability of Some Wheel-Related Graphs

open access: yesJournal of Mathematics, 2021
A vertex w∈VH distinguishes (or resolves) two elements (edges or vertices) a,z∈VH∪EH if dw,a≠dw,z. A set Wm of vertices in a nontrivial connected graph H is said to be a mixed resolving set for H if every two different elements (edges and vertices) of H ...
Bao-Hua Xing   +4 more
doaj   +1 more source

HS-integral and Eisenstein integral mixed circulant graphs

open access: yesTheory and Applications of Graphs, 2023
A mixed graph is called \emph{second kind hermitian integral} (\emph{HS-integral}) if the eigenvalues of its Hermitian-adjacency matrix of the second kind are integers.
Monu Kadyan, Bikash Bhattacharjya
doaj   +1 more source

Equivalence of the filament and overlap graphs of subtrees of limited trees [PDF]

open access: yesDiscrete Mathematics & Theoretical Computer Science, 2017
The overlap graphs of subtrees of a tree are equivalent to subtree filament graphs, the overlap graphs of subtrees of a star are cocomparability graphs, and the overlap graphs of subtrees of a caterpillar are interval filament graphs.
Jessica Enright, Lorna Stewart
doaj   +1 more source

The Spectral Distribution of Random Mixed Graphs

open access: yesAxioms, 2022
In this work, we propose a random mixed graph model Gn(p(n),q(n)) that incorporates both the classical Erdős-Rényi’s random graph model and the random oriented graph model.
Yue Guan   +7 more
doaj   +1 more source

Mixed graph edge coloring [PDF]

open access: yesDiscrete Mathematics, 2009
AbstractWe are interested in coloring the edges of a mixed graph, i.e., a graph containing unoriented and oriented edges. This problem is related to a communication problem in job-shop scheduling systems. In this paper we give general bounds on the number of required colors and analyze the complexity status of this problem. In particular, we provide NP-
Furmańczyk, Hanna   +3 more
openaire   +3 more sources

Colourings of $(m, n)$-coloured mixed graphs [PDF]

open access: yesDiscrete Mathematics & Theoretical Computer Science
A mixed graph is, informally, an object obtained from a simple undirected graph by choosing an orientation for a subset of its edges. A mixed graph is $(m, n)$-coloured if each edge is assigned one of $m \geq 0$ colours, and each arc is assigned one of ...
Gary MacGillivray   +2 more
doaj   +1 more source

Sequence mixed graphs

open access: yesDiscrete Applied Mathematics, 2017
A mixed graph can be seen as a type of digraph containing some edges (two opposite arcs). Here we introduce the concept of sequence mixed graphs, which is a generalization of both sequence graphs and iterated line digraphs. These structures are proven to be useful in the problem of constructing dense graphs or digraphs, and this is related to the ...
Dalfó Simó, Cristina   +2 more
openaire   +6 more sources

Home - About - Disclaimer - Privacy