Results 41 to 50 of about 3,789 (142)
Very weak solutions to hypoelliptic wave equations
Journal of Differential Equations, 2020 23 ...
Ruzhansky, M, Yessirkegenov, N
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Journal of the London Mathematical Society, Volume 111, Issue 5, May 2025.Abstract Using iterated uniform local completion, we introduce a notion of continuous CR$CR$ functions on locally closed subsets of reduced complex spaces, generalising both holomorphic functions and CR$CR$ functions on CR$CR$ submanifolds. Under additional assumptions of set‐theoretical weak pseudo‐concavity, we prove optimal maximum modulus ...
Mauro Nacinovich, Egmont Porten
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Parameter Estimation for Fractional Diffusion Process with Discrete Observations
Journal of Function Spaces, Volume 2019, Issue 1, 2019., 2019 This paper deals with the problem of estimating the parameters for fractional diffusion process from discrete observations when the Hurst parameter H is unknown. With combination of several methods, such as the Donsker type approximate formula of fractional Brownian motion, quadratic variation method, and the maximum likelihood approach, we give the ...
Yuxia Su, Yutian Wang, Yong H. Wu
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On linearization and uniqueness of preduals
Mathematische Nachrichten, Volume 298, Issue 3, Page 955-975, March 2025.Abstract We study strong linearizations and the uniqueness of preduals of locally convex Hausdorff spaces of scalar‐valued functions. Strong linearizations are special preduals. A locally convex Hausdorff space F(Ω)$\mathcal {F}(\Omega)$ of scalar‐valued functions on a nonempty set Ω$\Omega$ is said to admit a strong linearization if there are a ...
Karsten Kruse
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A comparison principle for nonlinear heat Rockland operators on graded groups
Bulletin of the London Mathematical Society, Volume 50, Issue 5, Page 753-758, October 2018., 2018 Abstract In this note we show a comparison principle for nonlinear heat Rockland operators on graded groups. We give a simple proof for it using purely algebraic relations. As an application of the established comparison principle we prove the global in t‐boundedness of solutions for a class of nonlinear equations for the heat p‐sub‐Laplacian on ...
Michael Ruzhansky, Durvudkhan Suragan
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Parameter Estimation of a Partially Observed Hypoelliptic Stochastic Linear System
MathematicsIn this article, we address the problem of the parameter estimation of a partially observed linear hypoelliptic stochastic system in continuous time, a relevant problem in various fields, including mechanical and structural engineering.
Nilton O. B. Ávido +1 more
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, 2011 For $d\geq 3$ we give an example of a constant coefficient surjective differential operator $P(D):\mathscr{D}'(X)\rightarrow\mathscr{D}'(X)$ over some open subset $X\subset\R^d$ such that $P^+(D):\mathscr{D}'(X\times\R)\rightarrow\mathscr{D}'(X\times\R)$
Kalmes, Thomas
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Hypoellipticity for a class of kinetic equations
Kyoto Journal of Mathematics, 2007 The authors consider the following linearized version of Boltzmann equation without angular cutoff: \[ Pu= \partial_t+ x\nabla_y u+ \sigma(-\widetilde\Delta_x)^\lambda u= f, \] where \((x,y)\in \mathbb{R}^{2n}\) and \(\sigma> 0\). Here \((-\widetilde\Delta_x)^\lambda\) is a Fourier multiplier with symbol \(|\eta|^{2\lambda}\) if \(|\eta|\geq 2\), and \(
Xu, Chao-Jiang, Morimoto, Yoshinori
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Bounds on Riesz Means of the Eigenvalues for Baouendi–Grushin Type Operators
International Journal of Mathematics and Mathematical Sciences, Volume 2025, Issue 1, 2025.The aim of this paper is to consider spectral inequalities of a class of Baouendi–Grushin type operators in cylinders. Such operators are hypoelliptic and we obtain non‐Weyl type inequalities depending on the rate of the degeneracy. We also give an example where all eigenvalues and eigenfunctions are computed explicitly.
Alaa Aljahili, Ari Laptev, Shikha Binwal
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Disuguaglianze di Harnack alla frontiera per equazioni di Kolmogorov
Bruno Pini Mathematical Analysis Seminar, 2011 We describe some recent results on the boundary regularity for hypoelliptic Kolmogorov equations. We prove boundary Harnack inequalities of the positive solutions to Kolmogorov equations vanishing on some relatively open subset of the boundary ...
Sergio Polidoro
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