Fixed Point Theorems for Set-Valued Mappings on TVS-Cone Metric Spaces

In the context of tvs-cone metric spaces, we prove a Bishop-Phelps and a Caristi's type theorem. These results allow us to prove a fixed point theorem for $(\delta, L)$-weak contraction according to a pseudo Hausdorff metric defined by means of a cone metric

PLEs from virtual ethnography of social web

This article presents an exploratory research based on the virtual ethnography from an environment of research and learning including new technologies. The ethnography is a method of qualitative research of social sciences that is mainly used in the socio-cultural anthropology, where it has its theoretical basis. The target was to explore the web 2.0 and its tools. The process of participant observation is by means of a blog, other tools and virtual communities. The result is a descriptive model of the web 2.0 based on a Personal Learning Environment which developed in the ethnographic experience.Postprint (published version

Glass transition in models with controlled frustration

A class of models with self-generated disorder and controlled frustration is studied. Between the trivial case, where frustration is not present at all, and the limit case, where frustration is present over every length scale, a region with local frustration is found where glassy dynamics appears. We suggest that in this region, the mean field model might undergo a p-spin like transition, and increasing the range of frustration, a crossover from a 1-step replica symmetry breaking to a continuous one might be observed.Comment: 4 pages, 6 figure

Deuteron properties from muonic atom spectroscopy

Leading order ($\alpha^4$) finite size corrections in muonic deuterium are evaluated within a few body formalism for the $\mu^- p n$ system in muonic deuterium and found to be sensitive to the input of the deuteron wave function. We show that this sensitivity, taken along with the precise deuteron charge radius determined from muonic atom spectroscopy can be used to determine the elusive deuteron D-state probability, $P_D$, for a given model of the nucleon-nucleon (NN) potential. The radius calculated with a $P_D$ of 4.3\% in the chiral NN models and about 5.7\% in the high precision NN potentials is favoured most by the $\mu^-d$ data.Comment: 14 pages, 2 figure

Segregation in hard spheres mixtures under gravity. An extension of Edwards approach with two thermodynamical parameters

We study segregation patterns in a hard sphere binary model under gravity subject to sequences of taps. We discuss the appearance of the ``Brazil nut'' effect (where large particles move up) and the ``reverse Brazil nut'' effects in the stationary states reached by ``tap'' dynamics. In particular, we show that the stationary state depends only on two thermodynamical quantities: the gravitational energy of the first and of the second species and not on the sample history. To describe the properties of the system, we generalize Edwards' approach by introducing a canonical distribution characterized by two configurational temperatures, conjugate to the energies of the two species. This is supported by Monte Carlo calculations showing that the average of several quantities over the tap dynamics and over such distribution coincide. The segregation problem can then be understood as an equilibrium statistical mechanics problem with two control parameters.Comment: 7 pages, 4 figure

Guess the score, fostering collective intelligence in the class

This paper proposes the use of serious games as a tool to enhance collective intelligence of undergraduate and graduate students. The development of social skills of individuals in a group is related to the performance of the collective intelligence of the group manifested through the shared and collaborative development of intellectual tasks [1]. Guess the Score GS, is a serious game implemented by means of an online tool, created to foster the development, collaboration and engagement of students. It's has been designed with the intention of facilitating the development of individual’s social skills in a group in order to promote education of collective intelligence. This paper concludes that the design of learning activities using serious games as a support tool in education, generate awareness about of utilities of gaming in the collective learning environment and the fostering of collective intelligence education.Postprint (published version