Results 11 to 20 of about 317,940 (197)
Graph Neural Networks for Voltage Stability Margins With Topology Flexibilities [PDF]
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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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.
Primož Potočnik, Micael Toledo
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Voltage graphs, weight systems and odd symmetry
Discrete Mathematics, 2001 A knot in the three-sphere \(S^{3}\) is called invertible if there exists an orientation preserving homeomorphism of \(S^{3}\) which takes the knot to itself with reverse orientation. It is an interesting problem whether Vassiliev invariants can detect the invertibility of a knot.
Leonid Plachta
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Trajectories entropy in dynamical graphs with memory [PDF]
Frontiers in Robotics and AI, 2016 In this paper we investigate the application of non-local graph entropy to evolving and dynamical graphs. The measure is based upon the notion of Markov diffusion on a graph, and relies on the entropy applied to trajectories originating at a specific ...
Francesco eCaravelli
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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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Knowledge graph-based method for identifying topological structure of low-voltage distribution network [PDF]
The Journal of Engineering, 2020 The correct topological relationship is crucial in the low-voltage distribution network, as the actual topological structure of the low-voltage distribution network changes frequently and tremendously due to the need of operation and maintenance, and it ...
Gao Zepu +4 more
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LDPC codes from voltage graphs [PDF]
2008 IEEE International Symposium on Information Theory, 2008 Several well-known structure-based constructions of LDPC codes, for example codes based on permutation and circulant matrices and in particular, quasi-cyclic LDPC codes, can be interpreted via algebraic voltage assignments. We explain this connection and show how this idea from topological graph theory can be used to give simple proofs of many known ...
Christine A. Kelley, Judy L. Walker
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Lifting Graph Automorphisms by Voltage Assignments
European Journal of Combinatorics, 2000 The authors provide the first systematic combinatorial treatment of the automorphism lifting problem in the context of graphs. They make consistent use of several new fundamental concepts: the action of the fundamental groupoid, the notion of a voltage space, various kinds of invariance of voltage spaces, and the geometry of the lifted actions by means
Aleksander Malnič +2 more
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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.
Natasha Jonoska +2 more
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Voltage lifts of graphs from a category theory viewpoint
Mathematica Slovaca, 2020 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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