Results 51 to 60 of about 477,790 (171)

On the spectral radius of VDB graph matrices

Vojnotehnički Glasnik, 2023
Introduction/purpose: Vertex-degree-based (VDB) graph matrices form a special class of matrices, corresponding to the currently much investigated vertex-degree-based (VDB) graph invariants. Some spectral properties of these matrices are investigated.
Ivan Gutman
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A generalization of spectral radius, numerical radius, and spectral norm

Linear Algebra and its Applications, 1987
The author defines three quantities, \(\rho\) (A), r(A), and \(\| A\|\), as scalar functions of a matrix A. These are \(\ell_ p\) norms of tuples formed respectively from the eigenvalues of A, the diagonal of a unitary similarity of A (that is, \(UAU^*)\), and the diagonal of a matrix unitarily equivalent to A (that is, UAV), where U, V are to be ...
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Degree Deviation and Spectral Radius

The Electronic Journal of Combinatorics
For a finite, simple, and undirected graph $G$ with $n$ vertices, $m$ edges, and largest eigenvalue $\lambda$, Nikiforov introduced the degree deviation of $G$ as$$s=\sum_{u\in V(G)}\left|d_G(u)-\frac{2m}{n}\right|.$$Contributing to a conjecture of Nikiforov, we show $\lambda-\frac{2m}{n}\leq \sqrt{\frac{2s}{3}}$.
Rautenbach, Dieter, Werner, Florian
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A formula for the inner spectral radius

International Journal of Mathematics and Mathematical Sciences, 2004
This note presents an asymptotic formula for the minimum of the moduli of the elements in the spectrum of a bounded linear operator acting on Banach space X.
S. Mahmoud Manjegani
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Droplet vertical sizing in warm clouds using passive optical measurements from a satellite [PDF]

Atmospheric Measurement Techniques, 2012
In this paper a new algorithm for the determination of the vertical distribution of the droplet effective radius in shallow warm clouds is proposed. The method is based on the fact that the spectral top-of-atmosphere reflectance in the near IR spectral ...
A. Kokhanovsky, V. V. Rozanov
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Numerical Radius Inequalities for Finite Sums of Operators

Demonstratio Mathematica, 2014
In this paper, we obtain some sharp inequalities for numerical radius of finite sums of operators. Moreover, we give some applications of our result in estimation of spectral radius. We also compare our results with some known results.
Mirmostafaee Alireza Kamel, Rahpeyma Omid Pourbahari, Omidvar Mohsen Erfanian   +2 more
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On local spectral radius [PDF]

Časopis pro pěstování matematiky, 1987
Let E be a Banach space and \(A\) a bounded linear operator on \(X\). Then for \(x\in A\) the local spectral radius \(r(A,x)\), of A with respect to \(x\) is defined by \[ r(A,x):=\overline{\lim}_{n\to \infty}\| A^ nx\|^{1/n}. \] Clearly, \(r(A,x)\leq r(A)\), the spectral radius of \(A\).
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The first three largest values of the spectral norm of oriented bicyclic graphs [PDF]

Discrete Mathematics Letters, 2023
Kun Wei, Jianping Li
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The Minimum Spectral Radius of Signless Laplacian of Graphs with a Given Clique Number

Discussiones Mathematicae Graph Theory, 2014
In this paper we observe that the minimal signless Laplacian spectral radius is obtained uniquely at the kite graph PKn−ω,ω among all connected graphs with n vertices and clique number ω.
Su Li, Li Hong-Hai, Zhang Jing
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First Hyper Zagreb Spectral Radii of Splitting and Shadow Graphs

Scientific Annals of Computer Science
The spectral radius RS of graph G is a spectral invariant derived from the eigenvalues of the associated matrix for a graph G. It is widely used in fields such as computer science, chemistry, biology, and network analysis.
Ahmad Bilal, Muhammad Mobeen Munir
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