Results 121 to 130 of about 306 (150)

On the distance signless Laplacian spectral radius of graphs

Linear and Multilinear Algebra, 2013
The distance signless Laplacian spectral radius of a connected graph G is the spectral radius of the distance signless Laplacian matrix of G, defined as where is the diagonal matrix of vertex transmissions of G and is the distance matrix of G. In this paper, we determine the graphs with minimum distance signless Laplacian spectral radius among the ...
Rundan Xing, Bo Zhou, Jianping Li
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Upper Bounds on the (Signless Laplacian) Spectral Radius of Irregular Weighted Graphs

Bulletin of the Malaysian Mathematical Sciences Society, 2020
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Shuiqun Xie, Xiaodan Chen, Xiuyu Li, Xiaoqian Liu   +3 more
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The signless Laplacian spectral radius of book-free graphs

Discrete Mathematics
For a positive integer \(k\), a book \(B_{k+1}\) is a graph consisting of \(k + 1\) triangles sharing a common edge. Let \(G\) be a \(B_{k+1}\)-free graph of order \(n \geq 49k^{2}-22k+4\). In this paper it is proved that the signless Laplacian spectral radius \(q(G) \leq (n+2k+\sqrt{(n-2k)^2+8k^2})/2\) with equality if and only if \(G = \overline{K_k}
Chen, Ming-Zhu, Jin, Ya-Lei, Zhang, Peng-Li   +2 more
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BOUNDS FOR SIGNLESS LAPLACIAN SPECTRAL RADIUS

2018
We consider weighted graphs, such as graphs where the edge weights are positive definite matrices of the same order in this paper. The signless Laplacian eigenvalues of a graph are the eigenvalues of the signless Laplacian matrix of a graph G. Then, we have give some bound and found different upper bounds for the signless Laplacian radius of weighted ...
Kabatas, Ulkunur, Kizilca, Fatma, Nurkahli, Semiha Basdas   +2 more
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Sharp bounds for the signless Laplacian spectral radius of digraphs

Applied Mathematics and Computation, 2014
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Lang, Weiwei, Wang, Ligong
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TWO SHARP UPPER BOUNDS FOR THE SIGNLESS LAPLACIAN SPECTRAL RADIUS OF GRAPHS

Discrete Mathematics, Algorithms and Applications, 2011
The signless Laplacian matrix of a graph is the sum of its degree diagonal and adjacency matrices. In this paper, we present a sharp upper bound for the spectral radius of the adjacency matrix of a graph. Then this result and other known results are used to obtain two new sharp upper bounds for the signless Laplacian spectral radius.
Chen, Ya-Hong, Pan, Rong-Ying, Zhang, Xiao-Dong   +2 more
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Signless Laplacian Spectral Radius and Some Hamiltonian Properties of Graphs

Journal of Discrete Mathematical Sciences and Cryptography, 2015
AbstractUsing upper bounds for the signless Laplacian spectral radius of graphs established by Yu et al. [9], Wang et al. [8], Liu et al. [7], and Li et al. [5], we in this note present sufficient conditions which are based on the signless Laplacian spectral radius for some Hamiltonian properties of graphs.
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On the signless Laplacian spectral radius of digraphs

2013
Let G = (V, E) be a digraph with n vertices and m arcs without loops and multiarcs, V = {v(1), v(2), ... , v(n)}. Denote the outdegree and average 2-outdegree of the vertex v(i) by d(i)(+) and m(i)(+), respectively. Let A (G) be the adjacency matrix and D (G) = diag (d(1)(+), d(2)(+), ... , d(n)(+)) be the diagonal matrix with outdegree of the vertices
Bozkurt, S. Burcu, Bozkurt, Durmus
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Some generalized Nordhaus–Gaddum-type results on the spectral radius and (signless) Laplacian spectral radius

Discrete Mathematics, Algorithms and Applications
Let [Formula: see text] be a simple graph, and [Formula: see text] be the spectral radius of [Formula: see text]. For [Formula: see text], a [Formula: see text]-edge (connected) decomposition [Formula: see text] is [Formula: see text] (connected) spanning subgraphs such that their edge sets form a [Formula: see text]-partition of the edge set of ...
Xianglei Chen, Changxiang He
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Semitransparent organic photovoltaics for building-integrated photovoltaic applications

Nature Reviews Materials, 2022
Yongxi Li
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