Search results for "Variables"

Weyl symbols and boundedness of Toeplitz operators

2019

International audience; We study Toeplitz operators on the Bargmann space, with Toeplitz symbols that are exponentials of inhomogeneous quadratic polynomials. It is shown that the boundedness of such operators is implied by the boundedness of the corresponding Weyl symbols.

Vector-Valued Hardy Spaces

2019

Given a Banach space X, we consider Hardy spaces of X-valued functions on the infinite polytorus, Hardy spaces of X-valued Dirichlet series (defined as the image of the previous ones by the Bohr transform), and Hardy spaces of X-valued holomorphic functions on l_2 ∩ B_{c0}. The chapter is dedicated to study the interplay between these spaces. It is shown that the space of functions on the polytorus always forms a subspace of the one of holomorphic functions, and these two are isometrically isomorphic if and only if X has ARNP. Then the question arises of what do we find in the side of Dirichlet series when we look at the image of the Hardy space of holomorphic functions. This is also answer…

Controlled diffeomorphic extension of homeomorphisms

2018

Let $\Omega$ be an internal chord-arc Jordan domain and $\varphi:\mathbb S\rightarrow\partial\Omega$ be a homeomorphism. We show that $\varphi$ has finite dyadic energy if and only if $\varphi$ has a diffeomorphic extension $h: \mathbb D\rightarrow \Omega$ which has finite energy.

Mapping properties for the Bargmann transform on modulation spaces

2010

We investigate mapping properties for the Bargmann transform and prove that this transform is isometric and bijective from modulation spaces to convenient Banach spaces of analytic functions.

Théorème de Gabrielov et fonctions log-exp-algébriques

1997

Resume Nous obtenons le theoreme de Wilkie sur les fonctions log-exp-algebriques du theoreme du complementaire ≪ explicite ≫ de Gabrielov, et de notre presentation geometrique du theoreme de van den Dries, Macintyre et Marker sur les fonctions log-exp-analytiques.

Volume estimate for a cone with a submanifold as vertex

1992

We give some estimates for the volume of a cone with vertex a submanifold P of a Riemannian or Kaehler manifold M. The estimates are functions of bounds of the mean curvature of P and the sectional curvature of M. They are sharp on cones having a basis which is contained in a tubular hypersurface about P in a space form or in a complex space form.

Efecto de supresión y mediación en el contexto de la intervención psicosocial: Diferencias, similitudes y ejemplos

2013

ResumenEl presente trabajo compara el efecto mediador y el supresor de una tercera variable. Ambos efectos parcelan la varianza de la variable dependiente (Y). La mediación es la reducción, tras introducir una tercera variable (Z) en el modelo, de la proporción de varianza explicada directamente por la variable independiente (X) en la variable criterio (Y) y la supresión es el incremento de la proporción de varianza explicada directamente por la independiente en la variable criterio, al incluir la tercera variable en el modelo. Se analizan las características y diferencias de cada efecto y se examina en qué situaciones se produce uno u otro. Cada situación, compuesta de tres variables corre…

2018

In recent decades, the massification and diversification of higher education have generated new challenges for the guidance of university students. The present study focuses on students’ experience...

Scale effects on plot runoff and soil erosion in a mediterranean environment

2017

Explaining scale effects for runoff and erosion improves our understanding of hydrological and erosion processes. In this investigation, plot-scale effects on event runoff per unit area, Qe, sediment concentration, Ce, and soil loss per unit area, SLe, were checked at the Sparacia (Italy) site. Similar information on the scale effects was obtained with different dependent variables, i.e., individual values of Qe, Ce, and SLe for each plot or the mean of their replicated values, and scale indicators, i.e., plot length, l, or plot area, A. The most common result, occurring for 57 to 62% of the events depending on the considered variable, was the lack of any scale effect. When scale effects we…

Riesz fractional integrals and complex fractional moments for the probabilistic characterization of random variables

2012

Abstract The aim of this paper is the probabilistic representation of the probability density function (PDF) or the characteristic function (CF) in terms of fractional moments of complex order. It is shown that such complex moments are related to Riesz and complementary Riesz integrals at the origin. By invoking the inverse Mellin transform theorem, the PDF or the CF is exactly evaluated in integral form in terms of complex fractional moments. Discretization leads to the conclusion that with few fractional moments the whole PDF or CF may be restored. Application to the pathological case of an α -stable random variable is discussed in detail, showing the impressive capability to characterize…