Results 31 to 40 of about 39,296 (257)
AIMS MathematicsLet $ d_u $ be the degree of a vertex $ u $ of a graph $ G $. The atom-bond sum-connectivity (ABS) index of a graph $ G $ is the sum of the numbers $ (1-2(d_v+d_w)^{-1})^{1/2} $ over all edges $ vw $ of $ G $. This paper gives the characterization of the
Tariq A. Alraqad +5 more
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An advance in infinite graph models for the analysis of transportation networks
International Journal of Applied Mathematics and Computer Science, 2016 This paper extends to infinite graphs the most general extremal issues, which are problems of determining the maximum number of edges of a graph not containing a given subgraph.
Cera Martín, Fedriani Eugenio M.
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Extremal Optimization of Graph Partitioning at the Percolation Threshold
, 1999 The benefits of a recently proposed method to approximate hard optimization problems are demonstrated on the graph partitioning problem. The performance of this new method, called Extremal Optimization, is compared to Simulated Annealing in extensive ...
Balberg I +24 more
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Ars Mathematica Contemporanea, 2012 A graph G is singular if the zero-one adjacency matrix has the eigenvalue zero. The multiplicity of the eigenvalue zero is called the nullity of G . For two vertices y and z of G , we call ( G , y , z ) a device with respect to y and z .
Irene Sciriha +4 more
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Tur\'an Graphs, Stability Number, and Fibonacci Index
, 2008 The Fibonacci index of a graph is the number of its stable sets. This parameter is widely studied and has applications in chemical graph theory. In this paper, we establish tight upper bounds for the Fibonacci index in terms of the stability number and ...
A. Knopfmacher +20 more
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On Acyclic Structures with Greatest First Gourava Invariant
Journal of Chemistry, 2022 Let ξ be a simple connected graph. The first Gourava index of graph ξ is defined as GO1ξ=∑μη∈Eξdμ+dη+dμdη, where dμ indicates the degree of vertex μ.
Mariam Imtiaz +4 more
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AKCE International Journal of Graphs and Combinatorics, 2023 For a connected simple graph G, the inverse degree index and forgotten index are defined as [Formula: see text] and [Formula: see text] respectively, where [Formula: see text] denotes the degree of vertex u in G.
Mohammad Ali Manian +2 more
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Graph Embedded Extreme Learning Machine [PDF]
IEEE Transactions on Cybernetics, 2016 In this paper, we propose a novel extension of the extreme learning machine (ELM) algorithm for single-hidden layer feedforward neural network training that is able to incorporate subspace learning (SL) criteria on the optimization process followed for the calculation of the network's output weights. The proposed graph embedded ELM (GEELM) algorithm is
Pitas, Ioannis +2 more
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Maximal tree and unicylic graph for Euler Sombor index with given diameter
AKCE International Journal of Graphs and CombinatoricsThe study of topological descriptors is essential for understanding the underlying structures of graphs and networks. Numerous numerical descriptors associated with graphs have been used to analyze their overall structure.
Zahid Raza +3 more
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P_{m}-saturated graphs with minimum size [PDF]
Opuscula Mathematica, 2004 By \(P_m\) we denote a path of order \(m\). A graph \(G\) is said to be \(P_m\)-saturated if \(G\) has no subgraph isomorphic to \(P_m\) and adding any new edge to \(G\) creates a \(P_m\) in \(G\). In 1986 L. Kászonyi and Zs.
Aneta Dudek, A. Paweł Wojda
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