Results 21 to 30 of about 172,487 (303)
On a Singular Robin Problem with Convection Terms
Advanced Nonlinear Studies, 2020 In this paper, the existence of smooth positive solutions to a Robin boundary-value problem with non-homogeneous differential operator and reaction given by a nonlinear convection term plus a singular one is established.
Guarnotta Umberto +2 more
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NeuroImage, 2023 The dependence of the diffusion MRI signal on the diffusion time carries signatures of restricted diffusion and exchange. Here we seek to highlight these signatures in the human brain by performing experiments using free gradient waveforms designed to be
Arthur Chakwizira +5 more
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Semilinear Elliptic Systems with Dependence on the Gradient [PDF]
Mediterranean Journal of Mathematics, 2018 We provide results on the existence, non-existence, multiplicity, and localization of positive radial solutions for semilinear elliptic systems with Dirichlet or Robin boundary conditions on an annulus. Our approach is topological and relies on the classical fixed point index. We present an example to illustrate our theory.
F. Cianciaruso, P. Pietramala
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Polarization-dependent tunneling of light in gradient optics [PDF]
Physical Review E, 2007 Reflection-refraction properties of photonic barriers, formed by dielectric gradient nanofilms, for inclined incidence of both S- and P-polarized electromagnetic (EM) waves are examined by means of exactly solvable models. We present generalized Fresnel formulae, describing the influence of the non-local dispersion on reflectance and transmittance of ...
Vladimir Kuzmiak +2 more
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A Liouville-Type Theorem for an Elliptic Equation with Superquadratic Growth in the Gradient
Advanced Nonlinear Studies, 2020 We consider the elliptic equation -Δu=uq|∇u|p{-\Delta u=u^{q}|\nabla u|^{p}} in ℝn{\mathbb{R}^{n}} for any p>2{p>2} and q>0{q>0}. We prove a Liouville-type theorem, which asserts that any positive bounded solution is constant.
Filippucci Roberta +2 more
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Quasilinear equations with dependence on the gradient
Nonlinear Analysis: Theory, Methods & Applications, 2009 Abstract We discuss the existence of positive solutions of the problem − ( q ( t ) φ ( u ′ ( t ) ) ) ′ = f ( t , u ( t ) , u ′ ( t ) ) for t ∈ ( 0 , 1 ) and u ( 0 ) = u ( 1 ) = 0 , where the nonlinearity f satisfies a superlinearity condition at 0 ...
Pedro Ubilla +3 more
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Confirming the Unusual Temperature Dependence of the Electric-Field Gradient in Zn
Crystals, 2022 The electric-field gradient (EFG) at nuclei in solids is a sensitive probe of the charge distribution. Experimental data, which previously only existed in insulators, have been available for metals with the development of nuclear measuring techniques ...
Heinz Haas +9 more
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Pressure-dependence of the aortic valve gradient
Journal of the American College of Cardiology, 1998 Dipendenza lineare el gradiente transaortico dalla pressione sistolica aortica e dalle resistenze ...
LEONI, LOIRA +6 more
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On periodic elliptic equations with gradient dependence
Communications on Pure & Applied Analysis, 2008 We construct entire solutions of $\Delta u=f(x,u,\nabla u)$ which are superpositions of odd, periodic functions and linear ones, with prescribed integer or rational slope.
Berti, M., Matzeu, M., Valdinoci, E.
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Training Neural Networks by Time-Fractional Gradient Descent
Axioms, 2022 Motivated by the weighted averaging method for training neural networks, we study the time-fractional gradient descent (TFGD) method based on the time-fractional gradient flow and explore the influence of memory dependence on neural network training. The
Jingyi Xie, Sirui Li
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