Results 31 to 40 of about 3,767,508 (152)
Proceedings in Applied Mathematics and Mechanics, Volume 26, Issue 4, December 2026.ABSTRACT We extend the kernel‐based symplectic predictor introduced by Herkert et al. (2026) to a parameter‐augmented setting in which the learned flow‐map surrogate depends not only on the state, but also on additional variables such as physical parameters and macro time‐step sizes. The method uses a product kernel ansatz on a parameter and macro step
Robin Herkert +2 more
wiley +1 more source
Inverse problems for semilinear elliptic PDE with a general nonlinearity a(x,u)$a(x,u)$
Transactions of the London Mathematical Society, Volume 13, Issue 1, December 2026.Abstract This article studies the inverse problem of recovering a nonlinearity in an elliptic equation Δu+a(x,u)=0$\Delta u + a(x,u) = 0$ from boundary measurements of solutions. Previous results based on first‐order linearization achieve this under a sign condition on ∂ua(x,u)$\partial _u a(x,u)$, and results based on higher order linearization ...
David Johansson +2 more
wiley +1 more source
Domain of Riesz mean in some spaces of double sequences
, 2018 In this study, we define the double sequence spaces (Mu)Rqt, (Cp)Rqt, (Cbp)Rqt and (Cr)Rqt as the domain of four dimensional Riesz mean Rqt in the spaces Mu, Cp, Cbp and Cr, respectively.
Yeşilkayagil, Medine +4 more
core +1 more source
On the Nonnegative Rank of Positive Operators
Mathematische Nachrichten, Volume 299, Issue 11, Page 3689-3704, November 2026.ABSTRACT In this paper, we introduce the concept of a nonnegative rank of a positive operator T:X→Y$T: X\rightarrow Y$ between ordered vector spaces. In the case of nonnegative matrices, our definition agrees with the standard definition of a nonnegative rank.
Roman Drnovšek, Marko Kandić
wiley +1 more source
Selector form of Weaver's conjecture and frame sparsification
Proceedings of the London Mathematical Society, Volume 133, Issue 5, November 2026.Abstract We show an extension of a probabilistic result of Marcus, Spielman, and Srivastava, which resolved the Kadison–Singer problem, to block diagonal positive semidefinite random matrices. We use this result to show several selector results, which generalize their partition counterparts.
Marcin Bownik
wiley +1 more source
MathematicsThe Stein–Weiss weighted inequality and the John–Nirenberg inequality are among the most important and widely applied results in harmonic analysis, underlying a broad range of developments in weighted norm estimates and the theory of bounded mean ...
Waqar Afzal +2 more
doaj +1 more source
Riesz Means on Graphs and Discrete Groups
Potential Analysis, 2011 For \(\alpha>0\) and \(R>0\), the Riesz mean of order \(\alpha\) is the operator defined by \[ m_{\alpha,R}(\Delta) = \int_0^2 m_{\alpha,R}(\lambda) \mathrm{d}E_\lambda \] where \(\Delta\) is the discrete Laplacian, \(\mathrm{d}E_\lambda\) is its spectral measure (so that \(\Delta = \int_0^2 \lambda \mathrm{d}E_\lambda\)) and \[ m_{\alpha,R}(\lambda) =
Fotiadis, Anestis +1 more
openaire +2 more sources
High order Riesz transforms and mean value formula for generalized translate operator [PDF]
, 2014 In this paper, the mean value formula depends on the Bessel-generalized shift operator corresponding to the solutions of the boundary value problem related to the multidimensional Bessel operator are studied.
Cansu Keskin +5 more
core +1 more source
K-Riesz bases and K-g-Riesz bases in Hilbert C∗-module
, 2023 This paper is devoted to studying the K-Riesz bases and the K-g-Riesz bases in Hilbert C∗-modules; we characterize the concept of K-Riesz bases by a bounded below operator and the standard orthonormal basis for Hilbert C∗-modules H.
Rossafi, Mohamed +2 more
core +1 more source
Hydrological Processes, Volume 40, Issue 10, October 2026.Answering the great catchment hysteresis challenge, we derive a catchment closure whose memory kernel follows from counting flow pathways and measuring how long water is detained. Applied to four Cumbrian micro‐catchments, it shows that the observed hysteresis index conflates event retention with genuine memory, and separating them weakens the inferred
Farrukh A. Chishtie
wiley +1 more source