Results 71 to 80 of about 11,357 (198)
Pseudodifferential Operators with Rough Symbols [PDF]
Journal of Fourier Analysis and Applications, 2009 In this work, we develop $L^p$ boundedness theory for pseudodifferential operators with rough (not even continuous in general) symbols in the $x$ variable. Moreover, the $B(L^p)$ operator norms are estimated explicitly in terms of scale invariant quantities involving the symbols.
openaire +2 more sources
The Metivier inequality and ultradifferentiable hypoellipticity
Mathematische Nachrichten, Volume 297, Issue 7, Page 2517-2531, July 2024.Abstract In 1980, Métivier characterized the analytic (and Gevrey) hypoellipticity of L2$L^2$‐solvable partial linear differential operators by a priori estimates. In this note, we extend this characterization to ultradifferentiable hypoellipticity with respect to Denjoy–Carleman classes given by suitable weight sequences. We also discuss the case when
Paulo D. Cordaro, Stefan Fürdös
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Non-radial functions, nonlocal operators and Markov processes over p-adic numbers
Universitas Scientiarum, 2019 The main goal of this article is to study a new class of nonlocal operators and the Cauchy problem for certain parabolic-type pseudodifferential equations naturally associated with them.
Leonardo Fabio Chacón-Cortés, Oscar Francisco Casas-Sánchez
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Invariant distributions and the transport twistor space of closed surfaces
Journal of the London Mathematical Society, Volume 109, Issue 5, May 2024.Abstract We study transport equations on the unit tangent bundle of a closed oriented Riemannian surface and their links to the transport twistor space of the surface (a complex surface naturally tailored to the geodesic vector field). We show that fibrewise holomorphic distributions invariant under the geodesic flow — which play an important role in ...
Jan Bohr +2 more
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Multiparameter Inversion: Cramer's Rule for Pseudodifferential Operators
International Journal of Geophysics, 2011 Linearized multiparameter inversion is a model-driven variant of amplitude-versus-offset analysis, which seeks to separately account for the influences of several model parameters on the seismic response.
Rami Nammour, William W. Symes
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Korteweg–de Vries waves in peridynamical media
Studies in Applied Mathematics, Volume 152, Issue 1, Page 376-403, January 2024.Abstract We consider a one‐dimensional peridynamical medium and show the existence of solitary waves with small amplitudes and long wavelength. Our proof uses nonlinear Bochner integral operators and characterizes their asymptotic properties in a singular scaling limit.
Michael Herrmann, Katia Kleine
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TASK Quarterly, 2017 We consider a generalization of the projection operator method for the case of the Cauchy problem in 1D space for systems of evolution differential equations of first order with variable coefficients.
SERGEY LEBLE, IRINA VERESHCHAGINA
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Prediction Method of Maximum Propagation Angle in Parabolic Equation Model over Irregular Terrain
International Journal of Antennas and Propagation, Volume 2024, Issue 1, 2024.The parabolic equation (PE) model is effective for predicting signal propagation over irregular terrains. The shift map method of the PE model is highly accurate and widely used for terrain propagation predictions. The maximum propagation angle is a crucial parameter of the shift map model.
Rui Zhang +5 more
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Pseudo-differential operators and equations in a discrete half-space
Mathematical Modelling and Analysis, 2018 We introduce a digital pseudo-differential operator acting in discrete Sobolev--Slobodetskii spaces and consider pseudo-differential equations with such operators in a discrete half-space.
Alexander V. Vasilyev +1 more
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International Journal of Antennas and Propagation, Volume 2024, Issue 1, 2024.In this article, the inverse diffraction parabolic equation (IDPE) model based on the finite difference method is proposed, which is first applied in the multiple nonradiation targets orientation technology. In principle, the electromagnetic signal propagating in the transmission path will produce a reflected signal back to the source end while ...
Qi Guo +5 more
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