Results 61 to 70 of about 256 (175)
Existence Results for a Class of Semilinear Elliptic Systems
, 2020 . In this paper, we study the existence of nontrivial solutions for the problem where Ω is bounded domain in R N and h 1 ,h 2 ∈ L 2 (Ω). The existence result is obtained by using the Leray-Schauder degree under the following condition on the ...
Moussaoui Abdelkrim, Khodja Brahim
core
Achievable multiplicity partitions in the inverse eigenvalue problem of a graph
Special Matrices, 2019 Associated to a graph G is a set 𝒮(G) of all real-valued symmetric matrices whose off-diagonal entries are nonzero precisely when the corresponding vertices of the graph are adjacent, and the diagonal entries are free to be chosen.
Adm Mohammad +5 more
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On minimum algebraic connectivity of graphs whose complements are bicyclic
Open Mathematics, 2019 The second smallest eigenvalue of the Laplacian matrix of a graph (network) is called its algebraic connectivity which is used to diagnose Alzheimer’s disease, distinguish the group differences, measure the robustness, construct multiplex model ...
Liu Jia-Bao +3 more
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The non-negative spectrum of a digraph
Open Mathematics, 2020 Given the adjacency matrix A of a digraph, the eigenvalues of the matrix AAT constitute the so-called non-negative spectrum of this digraph. We investigate the relation between the structure of digraphs and their non-negative spectra and associated ...
Alomari Omar +2 more
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A convergence analysis of SOR iterative methods for linear systems with weak H-matrices
Open Mathematics, 2016 It is well known that SOR iterative methods are convergent for linear systems, whose coefficient matrices are strictly or irreducibly diagonally dominant matrices and strong H-matrices (whose comparison matrices are nonsingular M-matrices).
Zhang Cheng-yi +2 more
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INTERVAL ITERATIVE METHODS FOR COMPUTING MOORE-PENROSE INVERSE ∗
, 2008 In this paper, we import interval method to the iteration for computing Moore-Penrose inverse of the full row (or column) rank matrix. Through modifying the classical Newton iteration by interval method, we can get better numerical results.
Xian Zhang, Yimin Wei, Jianfeng Cai
core
Bound for the largest singular value of nonnegative rectangular tensors
Open Mathematics, 2016 In this paper, we give a new bound for the largest singular value of nonnegative rectangular tensors when m = n, which is tighter than the bound provided by Yang and Yang in “Singular values of nonnegative rectangular tensors”, Front. Math.
He Jun +4 more
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Spectra of expansion graphs [PDF]
, 1999 . Replace certain edges of a directed graph by chains and consider the eect on the spectrum of the graph. It is shown that the spectral radius decreases monotonically with the expansion and that, for a strongly connected graph that is not a single cycle,
Hans Schneider +2 more
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Two new eigenvalue localization sets for tensors and theirs applications
Open Mathematics, 2017 A new eigenvalue localization set for tensors is given and proved to be tighter than those presented by Qi (J. Symbolic Comput., 2005, 40, 1302-1324) and Li et al. (Numer. Linear Algebra Appl., 2014, 21, 39-50).
Zhao Jianxing, Sang Caili
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Hardness Results and Spectral Techniques for Combinatorial Problems on Circulant Graphs
, 1998 We show that computing (and even approximating) MAXIMUM CLIQUE and MINIMUM GRAPH COLORING for circulant graphs is essentially as hard as in the general case.
Ivan Gerace +5 more
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