Results 1 to 10 of about 326,821 (208)
Generalised voltage graphs [PDF]
European Journal of Combinatorics, 2021 A graph with a semiregular group of automorphisms can be thought of as the derived cover arising from a voltage graph. Since its inception, the theory of voltage graphs and their derived covers has been a powerful tool used in the study of graphs with a significant degree of symmetry.
Potočnik, Primož, Toledo, Micael
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Semicubic cages and small graphs of even girth from voltage graphs [PDF]
Ars Mathematica Contemporanea, 2023 An \emph{$(3,m;g)$ semicubic graph} is a graph in which all vertices have degrees either $3$ or $m$ and fixed girth $g$. In this paper, we construct families of semicubic graphs of even girth and small order using two different techniques. The first technique generalizes a previous construction which glues cubic cages of girth $g$ together at remote ...
Aguilar, Flor +2 more
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Voltage Graphs, Group Presentations and Cages [PDF]
The Electronic Journal of Combinatorics, 2004 We construct smallest known trivalent graphs for girths 16 and 18. One construction uses voltage graphs, and the other coset enumeration techniques for group presentations.
Geoffrey Exoo
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Applications Of Ordinary Voltage Graph Theory To Graph Embeddability, Part 1 [PDF]
, 2015 We study embeddings of a graph $G$ in a surface $S$ by considering representatives of different classes of $H_1(S)$ and their intersections. We construct a matrix invariant that can be used to detect homological invariance of elements of the cycle space of a cellularly embedded graph.
Steven Schluchter
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Voltage Lifts of Graphs from a Category Theory Viewpoint [PDF]
Mathematica Slovaca, 2023 ABSTRACT We prove that the notion of a voltage graph lift comes from an adjunction between the category of voltage graphs and the category of group labeled graphs.
Gejza Jenča
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Lifting Voltages in Graph Covers [PDF]
We consider voltage digraphs, here referred to as graphs, whose edges are labeled with elements from a given group, and explore their derived graphs. Given two voltage graphs, with voltages in abelian groups, we establish a necessary and sufficient condition for their two derived graphs to be isomorphic.
Jonoska, Natasha +2 more
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Orientable Hamilton Cycle Embeddings of Complete Tripartite Graphs II: Voltage Graph Constructions and Applications [PDF]
Journal of Graph Theory, 2014 AbstractIn an earlier article the authors constructed a hamilton cycle embedding of in a nonorientable surface for all and then used these embeddings to determine the genus of some large families of graphs. In this two‐part series, we extend those results to orientable surfaces for all .
Ellingham, M. N., Schroeder, Justin Z.
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Design of Zero Voltage Switching Boost DC-DC Converter Using Bond Graph Model
Emitter: International Journal of Engineering Technology, 2020 The research in power supply design is moving towards improving efficiency by reducing losses. Another aspect of research in power converters is its modeling as it involves multiple domains such as electrical, mechanical, magnetic...etc.
Shaik Hussain Vali, R Kiranmayi
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Graph Neural Networks for Voltage Stability Margins With Topology Flexibilities
IEEE Open Access Journal of Power and Energy, 2023 High penetration of distributed energy resources (DERs) changes the flows in power grids causing thermal congestions which are managed by real-time corrective topology switching.
Kishan Prudhvi Guddanti +4 more
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Searching for Voltage Graph-Based LDPC Tailbiting Codes With Large Girth [PDF]
IEEE Transactions on Information Theory, 2012 The relation between parity-check matrices of quasi-cyclic (QC) low-density parity-check (LDPC) codes and biadjacency matrices of bipartite graphs supports searching for powerful LDPC block codes. Using the principle of tailbiting, compact representations of bipartite graphs based on convolutional codes can be found. Bounds on the girth and the minimum
Bocharova, Irina +4 more
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