A family of Dirichlet-Morrey spaces

To each weighted Dirichlet space $\mathcal{D}_p$, $0<p<1$, we associate a family of Morrey-type spaces ${\mathcal{D}}_p^{\lambda}$, $0< \lambda < 1$, constructed by imposing growth conditions on the norm of hyperbolic translates of functions. We indicate some of the properties of these spaces, mention the characterization in terms of boundary values, and study integration and multiplication operators on them.Comment: 18 page

Learning to detect video events from zero or very few video examples

In this work we deal with the problem of high-level event detection in video. Specifically, we study the challenging problems of i) learning to detect video events from solely a textual description of the event, without using any positive video examples, and ii) additionally exploiting very few positive training samples together with a small number of ``related'' videos. For learning only from an event's textual description, we first identify a general learning framework and then study the impact of different design choices for various stages of this framework. For additionally learning from example videos, when true positive training samples are scarce, we employ an extension of the Support Vector Machine that allows us to exploit ``related'' event videos by automatically introducing different weights for subsets of the videos in the overall training set. Experimental evaluations performed on the large-scale TRECVID MED 2014 video dataset provide insight on the effectiveness of the proposed methods.Comment: Image and Vision Computing Journal, Elsevier, 2015, accepted for publicatio

Generalized Hilbert Operators

If $g$ is an analytic function in the unit disc \D we consider the generalized Hilbert operator \hg defined by {equation*}\label{H-g} \mathcal{H}_g(f)(z)=\int_0^1f(t)g'(tz)\,dt. {equation*} We study these operators acting on classical spaces of analytic functions in \D . More precisely, we address the question of characterizing the functions $g$ for which the operator \hg is bounded (compact) on the Hardy spaces $H^p$, on the weighted Bergman spaces $A^p_\alpha$ or on the spaces of Dirichlet type $\mathcal D^p_\alpha$

Effective nucleon mass and the nuclear caloric curve

Assuming a schematic form of the nucleon effective mass as a function of nuclear excitation energy and mass, we provide a simple explanation for understanding the experimentally observed mass dependence of the nuclear caloric curve. It is observed that the excitation energy at which the caloric curve enters into a plateau region, could be sensitive to the nuclear mass evolution of the effective nucleon mass.Comment: 5 pages, 5 figures, Accepted for publication in Phys. Rev. C. Minor changes mad

Agricultural productivity growth in the Mediterranean and tests of convergence among countries

This paper measures agricultural productivity among a set of thirteen Mediterranean countries which includes two EU- 15 countries (Greece and Spain), another two EU- 25 (Cyprus and Malta) one country under accession negotiations (Turkey) and eight Middle East and North Africa (MENA) countries (Algeria, Egypt, Israel, Jordan, Libya, Morocco, Syria and Tunisia) from 1961 to 2002. The objective of the paper is twofold: Firstly, to analyse agricultural productivity growth in the Mediterranean countries by means of the sequential Malmquist Total Factor Productivity (TFP) index and secondly, to investigate whether this measure is converging among these countries. In terms of the first objective, TFP indices are decomposed into efficiency changes and technical changes, in an attempt to identify the best - practise countries and the overall effect of technological improvements. In terms of the second, both cross- section and time series tests of convergence are applied. The former include the conventional β- and σ- convergence tests, while for the latter, a new method proposed by Nahar and Inder (2002) that allows for country - specific estimates is used. Neither test finds evidence for unconditional convergence, but two distinctive periods, one prior and one after 1980 are recognized. The time series approach identifies four countries to be converging to the mean and another two to be diverging.Productivity growth, sequential Malmquist TFP, convergence., Productivity Analysis,

Populism in Greece and why the theory of the two extremes is wrong

Populism as a term reappeared in everyday public discourse in Greece with the first protests against the memorandum with IMF, EU and ECB and its concomitant austerity policies. The polarisation at the base of the populism/anti-populism dichotomy has been exacerbated on both a social and a political/ideological level. Every articulation of popular demands was denounced by the predominant power block as a populist one. All collective practices were stigmatised as populist and stripped of their political meaning. Everyone who distances himself even a minimum from the dominant neoliberal crisis management discourse was and is dismissed as a “populist”