Results 11 to 20 of about 3,087,593 (348)

𝕮-inverse of graphs and mixed graphs

Open Mathematics
This article introduces a generalization of the concept of inverse graphs applicable to both graphs and mixed graphs. Given a graph GG with adjacency matrix A(G)A\left(G), the inverse graph G−1{G}^{-1} is defined such that its adjacency matrix is similar
Alomari Omar, Abudayah Mohammad, Ghanem Manal   +2 more
doaj   +2 more sources

Mixed Graph Signal Analysis of Joint Image Denoising / Interpolation [PDF]

IEEE International Conference on Acoustics, Speech, and Signal Processing, 2023
A noise-corrupted image often requires interpolation. Given a linear denoiser and a linear interpolator, when should the operations be independently executed in separate steps, and when should they be combined and jointly optimized?
Niruhan Viswarupan, Gene Cheung, Fengbo Lan, Michael Brown   +3 more
semanticscholar   +1 more source

Mixed Graph Contrastive Network for Semi-supervised Node Classification [PDF]

ACM Transactions on Knowledge Discovery from Data, 2022
Graph Neural Networks (GNNs) have achieved promising performance in semi-supervised node classification in recent years. However, the problem of insufficient supervision, together with representation collapse, largely limits the performance of the GNNs ...
Xihong Yang, Yiqi Wang, Yue Liu, Yi Wen, Lingyuan Meng, Sihang Zhou, Xinwang Liu, En Zhu   +7 more
semanticscholar   +1 more source

The 2-colouring problem for $(m,n)$-mixed graphs with switching is polynomial [PDF]

Discrete Mathematics & Theoretical Computer Science, 2022
A mixed graph is a set of vertices together with an edge set and an arc set. An $(m,n)$-mixed graph $G$ is a mixed graph whose edges are each assigned one of $m$ colours, and whose arcs are each assigned one of $n$ colours. A \emph{switch} at a vertex $v$
Richard C Brewster, Arnott Kidner, Gary MacGillivray   +2 more
doaj   +1 more source

Incidence matrices and line graphs of mixed graphs

Special 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, Alomari Omar, Sander Torsten   +2 more
doaj   +1 more source

Integral mixed circulant graphs

Discrete Mathematics, 2023
A mixed graph is said to be \textit{integral} if all the eigenvalues of its Hermitian adjacency matrix are integer. The \textit{mixed circulant graph} $Circ(\mathbb{Z}_n,\mathcal{C})$ is a mixed graph on the vertex set $\mathbb{Z}_n$ and edge set $\{ (a,b): b-a\in \mathcal{C} \}$, where $0\not\in \mathcal{C}$.
Monu Kadyan, Bikash Bhattacharjya
openaire   +3 more sources

On bipartite‐mixed graphs [PDF]

Journal of Graph Theory, 2018
AbstractMixed graphs can be seen as digraphs that have both arcs and edges (or digons, that is, two opposite arcs). In this article, we consider the case where such graphs are bipartite. As main results, we show that in this context the Moore‐like bound is attained in the case of diameter , and that bipartite‐mixed graphs of diameter do not exist.
Dalfó Simó, Cristina, Fiol Mora, Miquel Àngel, López Lorenzo, Nacho   +2 more
openaire   +5 more sources

The Spectral Distribution of Random Mixed Graphs

Axioms, 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, Bo Cheng, Minfeng Chen, Meili Liang, Jianxi Liu, Jinxun Wang, Chao Yang, Li Zeng   +7 more
doaj   +1 more source

Identifying the Shortest Path of a Semidirected Graph and Its Application

Mathematics, 2022
The basic goal of this research is to find the shortest path of a semidirected graph and apply it to the road network system. In the field of graph theory, networks are described as directed graphs, undirected graphs, or a combination of both.
Rakhi Das, Laxminarayan Sahoo, Sovan Samanta, Vladimir Simic, Tapan Senapati   +4 more
doaj   +1 more source

Enumeration of Mixed Graphs [PDF]

Proceedings of the American Mathematical Society, 1966
and three oriented lines. An ordinary graph may be regarded as a mixed graph with no oriented lines, and an oriented graph as a mixed graph with no ordinary lines. Further, any digraph may be considered as a mixed graph by changing each symmetric pair of lines to an ordinary line.
Harary, Frank, Palmer, Edgar M.
openaire   +1 more source