Results 21 to 30 of about 612,388 (310)

Global bifurcation of sign-changing radial solutions of elliptic equations of order 2m in annular domains

AIMS Mathematics, 2020
In this paper we study the global bifurcation of sign-changing radial solutions for some semilinear elliptic problems of order 2m in an annulus with Dirichlet boundary conditions.
Ruyun Ma, Dongliang Yan, Liping Wei
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Bernstein-type theorems in hypersurfaces with constant mean curvature

Anais da Academia Brasileira de Ciências, 2000
By using the nodal domains of some natural function arising in the study of hypersurfaces with constant mean curvature we obtain some Bernstein-type theorems.
MANFREDO P. DO CARMO, DETANG ZHOU
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On eigenvalues and main eigenvalues of a graph [PDF]

Mathematica Moravica, 2000
Let G be a simple graph of order n and let λ1 ≥ λ 2 ≥ ··· ≥ n and λ1 ≥ λ2 ≥ ··· ≥ λn be its eigenvalues with respect to the ordinary adjacency matrix A = A(G) and the Seidel adjacency matrix A*=A*(G), respectively. Using the Courant-Weyl inequalities we prove that λ n+1−i Є [−λ i−1, λ i+1−1] and λ n*+1−i Є [−2 λ i−1,−2 λ i+1−1] for i = 1, 2,..., n−1 ...
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Lassoing eigenvalues

Biometrika, 2020
Summary The properties of penalized sample covariance matrices depend on the choice of the penalty function. In this paper, we introduce a class of nonsmooth penalty functions for the sample covariance matrix and demonstrate how their use results in a grouping of the estimated eigenvalues.
Tyler, David E., Yi, Mengxi
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OPTIMIZATION OF 3D LOCAL ORIENTATION MAP CALCULATION IN THE MATLAB FRAMEWORK

Informatyka, Automatyka, Pomiary w Gospodarce i Ochronie Środowiska, 2015
This paper presents the development and evaluation of a new approach toward the optimization of 3D local orientation map calculation in the Matlab framework. This new approach can be detailed as: optimize eigenvector calculation for PCA analysis of X-ray
Ranya Al Darwich, Laurent Babout
doaj   +1 more source

Evolution of the first eigenvalue of the Laplace operator and the p-Laplace operator under a forced mean curvature flow

Open Mathematics, 2020
In this paper, we discuss the monotonicity of the first nonzero eigenvalue of the Laplace operator and the p-Laplace operator under a forced mean curvature flow (MCF).
Qi Xuesen, Liu Ximin
doaj   +1 more source

On a class of H-selfadjont random matrices with one eigenvalue of nonpositive type [PDF]

, 2012
Large H-selfadjoint random matrices are considered. The matrix $H$ is assumed to have one negative eigenvalue, hence the matrix in question has precisely one eigenvalue of nonpositive type.
Wojtylak, Michal
core   +1 more source

Eigenvalues and pseudo-eigenvalues of Toeplitz matrices

Linear Algebra and its Applications, 1992
AbstractThe eigenvalues of a nonhermitian Toeplitz matrix A are usually highly sensitive to perturbations, having condition numbers that increase exponentially with the dimension N. An equivalent statement is that the resolvent (zI − A)−1 of a Toeplitz matrix may be much larger in norm than the eigenvalues alone would suggest-exponentially large as a ...
Lloyd N. Trefethen, Lothar Reichel
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Eigenvalue comparisons in Steklov eigenvalue problem and some other eigenvalue estimates [PDF]

Revista Matemática Complutense, 2019
Comments are welcome. 24 pages.
Feng Du, Chuanxi Wu, Yan Zhao, Jing Mao, Jing Mao   +4 more
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A pathological example in Nonlinear Spectral Theory [PDF]

, 2017
We construct an open set $\Omega\subset\mathbb{R}^N$ on which an eigenvalue problem for the $p-$Laplacian has not isolated first eigenvalue and the spectrum is not discrete.
Brasco, Lorenzo, Franzina, Giovanni
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