Broken planar Skyrmions — statics and dynamics.

The broken planar Skyrme model is a theory that breaks global O (3) symmetry to the dihedral group D N . It has been shown that the single soliton solution is formed of N constituent parts, named partons, that are topologically confined. The multisoliton solutions have already been computed for N = 3 and were shown to be related to polyiamonds. We extend this for larger N and demonstrate that this polyform structure continues (planar figures formed by regular N -gons joined along their edges, of which polyiamonds are the N = 3 subset). Furthermore, we numerically simulate the dynamics of this model for the first time. It will be demonstrated that the time dependent behaviour of these solutions can be broken down into the interactions of its constituent partons, with certain collisions exhibiting parton exchange. The results are then compared with those of the standard planar Skyrme model

Streaky 3D Structures in the Boundary Layer

It has been recently shown [Choi, Nature, April 06 - Cossu, PRL, February 06] that 3D streaky structures in the boundary layer can remain laminar longer than the 2D Blasius °ow. The aim of this investigation is to study the possibility of promoting these 3D streaky structures via surface roughness, computing them and evaluat- ing the resulting stabilization using the Reduced Navier Stokes equations (RNS). The RNS are derived from Navier-Stokes making use of the fact that two very di®erent scales are present: one slow (streamwise direc- tion) and two short (spanwise and wall-normal direction). The RNS allows us to perform these 3D computations in a standard PC, without using CPU costly DNS simulations

Computation of nonlinear streaky structures in boundary layer flow

In this work, the Reduced Navier Stokes (RNS) are numerically integrated, and used to calculate nonlinear finite amplitude streaks. These structures are interesting since they can have a stabilizing effect and delay the transition to the turbulent regime. RNS formulation is also used to compute the family of nonlinear intrinsic streaks that emerge from the leading edge in absence of any external perturbation. Finally, this formulation is generalized to include the possibility of having a curved bottom wal

"Zelometeorium" y "Meteoridium" ("Bryophyta", "Brachytheciaceae") en Argentina

The genera Zelometeorium and Meteoridium are studied for Argentina based on herbarium specimens and on specimens collected during field expeditions (2006-2010) from the ecoregion the Yungas (Jujuy, Salta, Catamarca and Tucumán provinces in the Northwest) to the ecoregion Paranense (Corrientes, Misiones provinces in the northeast of Argentina). Zelometeorium ambiguum is new record for Catamarca province and its references in Jujuy, Salta, Tucumán and Misiones are confirmed. Z. patulum is new record for Argentina and Meteoridium remotifolium is new record for Salta and Misiones and its presence in Tucumán is confirmed. Meteoriopsis characeae var. nigrescens and Meteoriopsis characeae var. tenuis, should be excluded for the Argentinian bryological flora because both are synonyms taxa of Zelometeorium ambiguum. Keys, descriptions, illustrations, photographs and distribution maps of these taxa are provided.Se ha realizado el estudio de los géneros Zelometeorium y Meteoridium basado en los especímenes registrados en los herbarios y de los recolectados durante las campañas (2006-2010) realizadas desde la ecoregión de las Yungas (provincias de Jujuy, Salta, Catamarca y Tucumán al noroeste de Argentina ) hasta la ecoregión Paranense (provincias de Corrientes y Misiones al Nordeste). Zelometeorium ambiguum es nueva aportación para la provincia de Catamarca, y se confirman sus referencias en Salta, Tucumán y Misiones; Z. patulum es novedad para Argentina y Meteoridium remotifolium es nueva aportación para Misiones y Salta y se confirma su presencia en Tucumán. Meteoriopsis characeae var. nigrescens y Meteoriopsis characeae var. tenuis, deben ser excluidos de la flora briológica argentina por ser ambos taxones sinónimos de Zelometeorium ambiguum. Se aportan claves, descripciones, figuras, fotografías y mapas de distribución de estos taxones

Experimental phase functions of mm-sized cosmic dust grains

We present experimental phase functions of three types of millimeter-sized dust grains consisting of enstatite, quartz and volcanic material from Mount Etna, respectively. The three grains present similar sizes but different absorbing properties. The measurements are performed at 527 nm covering the scattering angle range from 3 to 170 degrees. The measured phase functions show two well defined regions i) soft forward peaks and ii) a continuous increase with the scattering angle at side- and back-scattering regions. This behavior at side- and back-scattering regions are in agreement with the observed phase functions for the Fomalhaut and HR 4796A dust rings. Further computations and measurements (including polarization) for millimeter sized-grains are needed to draw some conclusions about the fluffy or compact structure of the dust grains

DESCENTRALIZACIÓN Y RECUPERACIÓN SOCIAL DEL TERRITORIO

Twenty years after the Colombian PoliticalConstitution was signed, the current researchaims at analyzing the state of thatdecentralizing alternative, taking into accounttwo essential elements – the democratization inthe exercise of the local power, and the responsibilities and the fiscal autonomy of the territorial entities, to the light of a governmental strategy of the Uribe Government – the socalled Social Recovery of the Territory -, within a concrete plan of a national government – the Frame Plan for the Integral Recovery of “Montes de María–” and several Municipal Development Plans, such as those from El Carmen de Bolívar, San Onofre, San Jacinto and Ovejas

Caracterización de un AGV (vehículo guiado automáticamente) en el sistema de manufactura flexible, caso Centro Tecnológico de Automatización CTAI de la Pontificia Universidad Javeriana

Ingeniero (a) IndustrialPregrad