Results 31 to 40 of about 1,274,829 (283)
SNR walls in eigenvalue-based spectrum sensing
EURASIP Journal on Wireless Communications and Networking, 2017 Various spectrum sensing approaches have been shown to suffer from a so-called signal-to-noise ratio (SNR)-wall, an SNR value below which a detector cannot perform robustly no matter how many observations are used. Up to now, the eigenvalue-based maximum-
Andreas Bollig +3 more
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On the Neumann eigenvalues for second-order Sturm–Liouville difference equations
Advances in Difference Equations, 2020 The paper is concerned with the Neumann eigenvalues for second-order Sturm–Liouville difference equations. By analyzing the new discriminant function, we show the interlacing properties between the periodic, antiperiodic, and Neumann eigenvalues ...
Yan-Hsiou Cheng
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On the second minimizing graph in the set of complements of trees
AKCE International Journal of Graphs and Combinatorics, 2019 Let G be a graph of order n and A(G)=[ai,j]be its adjacency matrix such that ai,j=1 if viis adjacent to vjand ai,j=0 otherwise, where 1≤i,j≤n. In a certain family of graphs, a graph is called minimizing (or second minimizing) if the least eigenvalue of ...
M. Javaid
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An eigenvalue localization set for tensors and its applications
Journal of Inequalities and Applications, 2017 A new eigenvalue localization set for tensors is given and proved to be tighter than those presented by Li et al. (Linear Algebra Appl. 481:36-53, 2015) and Huang et al. (J. Inequal. Appl. 2016:254, 2016).
Jianxing Zhao, Caili Sang
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Minimum number of distinct eigenvalues of graphs [PDF]
The Electronic Journal of Linear Algebra, 2013 The minimum number of distinct eigenvalues, taken over all real symmetric matrices compatible with a given graph G, is denoted by q(G). Using other parameters related to G, bounds for q(G) are proven and then applied to deduce further properties of q(G). It is shown that there is a great number of graphs G for which q(G) = 2.
Ahmadi, Bahman +5 more
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On completely regular codes with minimum eigenvalue in geometric graphs
Discrete Mathematics, 2023 We prove that any completely regular code with minimum eigenvalue in any geometric graph G corresponds to a completely regular code in the clique graph of G. Studying the interrelation of these codes, a complete characterization of the completely regular codes in the Johnson graphs J(n,w) with covering radius w-1 and strength 1 is obtained.
Ivan Yu. Mogilnykh +1 more
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On the minimum number of distinct eigenvalues of a threshold graph [PDF]
Linear Algebra and its Applications, 2022 For a graph $G$, we associate a family of real symmetric matrices, $S(G)$, where for any $A\in S(G)$, the location of the nonzero off-diagonal entries of $A$ are governed by the adjacency structure of $G$. Let $q(G)$ be the minimum number of distinct eigenvalues over all matrices in $S(G)$.
Shaun Fallat, Seyed Ahmad Mojallal
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On large-scale diagonalization techniques for the Anderson model of localization [PDF]
, 2006 We propose efficient preconditioning algorithms for an eigenvalue problem arising in quantum physics, namely the computation of a few interior eigenvalues and their associated eigenvectors for large-scale sparse real and symmetric indefinite matrices of ...
Bollhofer, Matthias +8 more
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HUBO formulations for solving the eigenvalue problem
Results in Control and Optimization, 2023 Solving the eigenvalue problem is particularly important in almost all fields of science and engineering. With the development of quantum computers, multiple algorithms have been proposed for this purpose.
Kyungtaek Jun, Hyunju Lee
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Minimum Supports of Eigenfunctions with the Second Largest Eigenvalue of the Star Graph [PDF]
The Electronic Journal of Combinatorics, 2020 The Star graph $S_n$, $n\ge 3$, is the Cayley graph on the symmetric group $Sym_n$ generated by the set of transpositions $\{(12),(13),\ldots,(1n)\}$. In this work we study eigenfunctions of $S_n$ corresponding to the second largest eigenvalue $n-2$.
Vladislav V. Kabanov +3 more
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