Results 11 to 20 of about 2,362,134 (317)
Voltage graphs, weight systems and odd symmetry
Discrete Mathematics, 2001 Abstract We present combinatorial constructions of the weight systems associated with Vassiliev link invariants by means of natural maps from the space of equivalence classes of Chinese characters to the spaces of marked diagrams. The weight systems coming from those maps are described.
Leonid Plachta
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VolTAGE: Volatility Forecasting via Text Audio Fusion with Graph Convolution Networks for Earnings Calls [PDF]
Conference on Empirical Methods in Natural Language Processing, 2020 Natural language processing has recently made stock movement forecasting and volatility forecasting advances, leading to improved financial forecasting.
Ramit Sawhney +5 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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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 AbstractThe problem of lifting graph automorphisms along covering projections and the analysis of lifted groups is considered in a purely combinatorial setting. The main tools employed are: (1) a systematic use of the fundamental groupoid; (2) unification of ordinary, relative and permutation voltage constructions into the concept of a voltage space ...
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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On the girth of voltage graph lifts
European Journal of Combinatorics, 2011 AbstractWe study the potential and limitations of the voltage graph construction for producing small regular graphs of large girth. We determine the relation between the girth of the base graph and the lift, and we show that any base graph can be lifted to a graph of arbitrarily large girth.
G. Exoo, Robert Jajcay
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Energies, 2020 The use of a Graph Trace Analysis (GTA)-based power flow for analyzing the voltage stability of integrated Transmission and Distribution (T&D) networks is discussed in the context of distributed Photovoltaic (PV) generation.
Bilal Ahmad Bhatti +2 more
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Semicubic cages and small graphs of even girth from voltage graphs
, 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 ...
Flor Aguilar +2 more
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