Now showing items 115-134 of 240

• #### New bounds for bilinear Calderón-Zygmund operators and applications ﻿

(2016-11-25)
In this work we extend Lacey’s domination theorem to prove the pointwise control of bilinear Calderón–Zygmund operators with Dini–continuous kernel by sparse operators. The precise bounds are carefully tracked following ...
• #### Nondegeneracy of heteroclinic orbits for a class of potentials on the plane ﻿

(2021)
In the scalar case, the nondegeneracy of heteroclinic orbits is a well-known property, commonly used in problems involving nonlinear elliptic, parabolic or hyperbolic P.D.E. On the other hand, Schatzman proved that in the ...
• #### Nonlocal discrete diffusion equations and the fractional discrete Laplacian, regularity and applications ﻿

(2018)
The analysis of nonlocal discrete equations driven by fractional powers of the discrete Laplacian on a mesh of size $h>0$ $(-\Delta_h)^su=f,$ for $u,f:\Z_h\to\R$, $0<s<1$, is performed. The pointwise nonlocal ...
• #### A note on generalized Fujii-Wilson conditions and BMO spaces ﻿

(2020-07-01)
In this note we generalize the definition of the Fujii-Wilson condition providing quantitative characterizations of some interesting classes of weights, such as A∞, A∞weak and Cp, in terms of BMO type spaces suited to them. ...
• #### A note on generalized Poincaré-type inequalities with applications to weighted improved Poincaré-type inequalities ﻿

(2020)
The main result of this paper supports a conjecture by C. P\'erez and E. Rela about the properties of the weight appearing in their recent self-improving result of generalized inequalities of Poincar\'e-type in the Euclidean ...
• #### A note on the off-diagonal Muckenhoupt-Wheeden conjecture ﻿

(2016-07-01)
We obtain the off-diagonal Muckenhoupt-Wheeden conjecture for Calderón-Zygmund operators. Namely, given $1 < p < q < \infty$ and a pair of weights $(u; v)$, if the Hardy-Littlewood maximal function satisfies the following ...
• #### Numerical approximation of the fractional Laplacian on R using orthogonal families ﻿

(2020-12-01)
In this paper, using well-known complex variable techniques, we compute explicitly, in terms of the F12 Gaussian hypergeometric function, the one-dimensional fractional Laplacian of the complex Higgins functions, the complex ...
• #### The observational limit of wave packets with noisy measurements ﻿

(2019)
The authors consider the problem of recovering an observable from certain measurements containing random errors. The observable is given by a pseudodifferential operator while the random errors are generated by a Gaussian ...
• #### On a hyperbolic system arising in liquid crystal modelling ﻿

(2017-11)
We consider a model of liquid crystals, based on a nonlinear hyperbolic system of differential equations, that represents an inviscid version of the model proposed by Qian and Sheng. A new concept of dissipative solution ...
• #### On a probabilistic model for martensitic avalanches incorporating mechanical compatibility ﻿

(2021-07-01)
Building on the work by Ball et al (2015 MATEC Web of Conf. 33 02008), Cesana and Hambly (2018 A probabilistic model for interfaces in a martensitic phase transition arXiv:1810.04380), Torrents et al (2017 Phys. Rev. E 95 ...
• #### On a sharp Poincare-type inequality on the 2-sphere and its application in micromagnetics ﻿

(2019-08-21)
The main aim of this note is to prove a sharp Poincaré-type inequality for vector-valued functions on $\mathbb{S}^2$ that naturally emerges in the context of micromagnetics of spherical thin films.
• #### On Bloom type estimates for iterated commutators of fractional integrals ﻿

(2018-04)
In this paper we provide quantitative Bloom type estimates for iterated commutators of fractional integrals improving and extending results from [15]. We give new proofs for those inequalities relying upon a new sparse ...
• #### On extension problem, trace hardy and Hardy’s inequalities for some fractional Laplacians ﻿

(2019-09)
We obtain generalised trace Hardy inequalities for fractional powers of general operators given by sums of squares of vector fields. Such inequalities are derived by means of particular solutions of an extended equation ...
• #### On pointwise and weighted estimates for commutators of Calderón-Zygmund operators ﻿

(2017)
In recent years, it has been well understood that a Calderón-Zygmund operator T is pointwise controlled by a finite number of dyadic operators of a very simple structure (called the sparse operators). We obtain a similar ...
• #### On sums involving Fourier coefficients of Maass forms for SL(3,Z) ﻿

(2016-09-10)
We derive a truncated Voronoi identity for rationally additively twisted sums of Fourier coefficients of Maass forms for SL(3,Z), and as an application obtain a pointwise estimate and a second moment estimate for the sums ...
• #### On the absolute divergence of Fourier series in the infinite dimensional torus ﻿

(2019-03-22)
• #### On the controllability of Partial Differential Equations involving non-local terms and singular potentials ﻿

(2016-12-12)
In this thesis, we investigate controllability and observability properties of Partial Differential Equations describing various phenomena appearing in several fields of the applied sciences such as elasticity theory, ...
• #### On the energy of critical solutions of the binormal flow ﻿

(2019-07-20)
The binormal flow is a model for the dynamics of a vortex filament in a 3-D inviscid incompressible fluid. The flow is also related with the classical continuous Heisen- berg model in ferromagnetism, and the 1-D cubic Schr ...
• #### On the energy of critical solutions of the binormal flow ﻿

(2020-07-02)
The binormal flow is a model for the dynamics of a vortex filament in a 3-D inviscid incompressible fluid. The flow is also related with the classical continuous Heisenberg model in ferromagnetism, and the 1-D cubic ...