Results 1 to 10 of about 2,462 (139)
SegFormer-based boundary-aware polyp segmentation with adaptive multi-branch fusion [PDF]
Scientific ReportsAccurate definition of colorectal polyps for the prevention of cancer is challenging due to high variability in appearance and indefinite boundaries. In this work, we present a SegFormer-aided framework comprising a transformer encoder (SegFormer-B4) and
Mahdi Ouria +3 more
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Eigenvalues and bifurcation for Neumann problems with indefinite weights
Electronic Journal of Differential Equations, 2021 We consider eigenvalue problems and bifurcation of positive solutions for elliptic equations with indefinite weights and with Neumann boundary conditions. We give complete results concerning the existence and non-existence of positive solutions for the superlinear coercive and non-coercive problems, showing a surprising complementarity of the ...
Marta Calanchi, Bernhard Ruf
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Eigenvalue problems for the p-Laplacian with indefinite weights
Electronic Journal of Differential Equations, 2001 We consider the eigenvalue problem $-Delta_p u=lambda V(x) |u|^{p-2} u, uin W_0^{1,p} (Omega)$ where $p>1$, $Delta_p$ is the p-Laplacian operator, $lambda >0$, $Omega$ is a bounded domain in $mathbb{R}^N$ and $V$ is a given function in $L^s (Omega)$ ($s$
Mabel Cuesta
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Spectrum of a Class of Difference Operators with Indefinite Weights
Journal of Applied Mathematics and Physics, 2020 In this study, we use analytical methods and Sylvester inertia theorem to research a class of second order difference operators with indefinite weights and coupled boundary conditions. The eigenvalue problem with sign-changing weight has lasted a long time.
Congmin Yang, Yunlan Gao, Kang Sun
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Degenerate Elliptic Eigenvalue Problems with Indefinite Weights [PDF]
Mediterranean Journal of Mathematics, 2008 The purpose of this paper is to provide a careful and accessible exposition of the Kreĭn and Rutman Theory of degenerate elliptic eigenvalue problems with indefinite weights that model population dynamics in environments with spatial heterogeneity.
Kazuaki Taira
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Nodal solutions of weighted indefinite problems [PDF]
Journal of Evolution Equations, 2020 This paper analyzes the structure of the set of nodal solutions of a class of one-dimensional superlinear indefinite boundary values problems with an indefinite weight functions in front of the spectral parameter. Quite astonishingly, the associated high order eigenvalues might not be concave as it is the lowest one.
M. Fencl, J. López-Gómez
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EIGENVALUE HOMOGENISATION PROBLEM WITH INDEFINITE WEIGHTS [PDF]
Bulletin of the Australian Mathematical Society, 2015 In this work we study the homogenisation problem for nonlinear elliptic equations involving$p$-Laplacian-type operators with sign-changing weights. We study the asymptotic behaviour of variational eigenvalues which consist of a double sequence of eigenvalues.
Fernandez Bonder, Julian +2 more
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Asymmetric elliptic problems with indefinite weights [PDF]
Annales de l'Institut Henri Poincaré C, Analyse non linéaire, 2002 We prove the existence of a first nontrivial eigenvalue for an asymmetric elliptic problem with weights involving the laplacian (cf. (1.2) below) or more generally the p -laplacian (cf. (1.3) below).
Gossez, Jean-Pierre +3 more
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Mathematics, 2023 Full-duplex (FD) communication has been shown to provide an increased achievable rate, while millimeter wave (mmWave) communications benefit from a large available bandwidth that further improves the achievable rate.
Abdulah Jeza Aljohani +4 more
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On the Fučík spectrum with indefinite weights
Differential and Integral Equations, 2001 19 pages, to appear in Diff.
Gossez, Jean-Pierre, Alif, Mohssine
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