A virtual element method for the vibration problem of Kirchhoff plates

The aim of this paper is to develop a virtual element method (VEM) for the vibration problem of thin plates on polygonal meshes. We consider a variational formulation relying only on the transverse displacement of the plate and propose an $H^2(\Omega)$ conforming discretization by means of the VEM which is simple in terms of degrees of freedom and coding aspects. Under standard assumptions on the computational domain, we establish that the resulting schemeprovides a correct approximation of the spectrum and prove optimal order error estimates for the eigenfunctions and a double order for the eigenvalues. The analysis restricts to simply connected polygonal clamped plates, not necessarily convex. Finally, we report several numerical experiments illustrating the behaviour of the proposed scheme and confirming our theoretical results on different families of meshes. Additional examples of cases not covered by our theory are also presented

LAGO: The Latin American giant observatory

The Latin American Giant Observatory (LAGO) is an extended cosmic ray observatory composed of a network of water-Cherenkov detectors (WCD) spanning over different sites located at significantly different altitudes (from sea level up to more than 5000 m a.s.l.) and latitudes across Latin America, covering a wide range of geomagnetic rigidity cut-offs and atmospheric absorption/reaction levels. The LAGO WCD is simple and robust, and incorporates several integrated devices to allow time synchronization, autonomous operation, on board data analysis, as well as remote control and automated data transfer. This detection network is designed to make detailed measurements of the temporal evolution of the radiation flux coming from outer space at ground level. LAGO is mainly oriented to perform basic research in three areas: high energy phenomena, space weather and atmospheric radiation at ground level. It is an observatory designed, built and operated by the LAGO Collaboration, a non-centralized collaborative union of more than 30 institutions from ten countries. In this paper we describe the scientific and academic goals of the LAGO project - illustrating its present status with some recent results - and outline its future perspectives.Fil: Sidelnik, Iván Pedro. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte; Argentina. Comisión Nacional de Energía Atómica. Gerencia del Área de Energía Nuclear. Gerencia de Ingeniería Nuclear (CAB). División Neutrones y Reactores; Argentina. Comisión Nacional de Energía Atómica. Gerencia del Área de Energía Nuclear. Instituto Balseiro; ArgentinaFil: Asorey, Hernán Gonzalo. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Tecnología en Detección y Astropartículas. Comisión Nacional de Energía Atómica. Instituto de Tecnología en Detección y Astropartículas. Universidad Nacional de San Martín. Instituto de Tecnología en Detección y Astropartículas; Argentina. Comisión Nacional de Energía Atómica. Gerencia del Área de Energía Nuclear. Instituto Balseiro; ArgentinaFil: Lago Collaboration. Latin American Giant Observatory; Argentin

Numerical simulation of density-driven flow and heat transport processes in porous media using the network method

Density-driven flow and heat transport processes in 2-D porous media scenarios are governed by coupled, non-linear, partial differential equations that normally have to be solved numerically. In the present work, a model based on the network method simulation is designed and applied to simulate these processes, providing steady state patterns that demonstrate its computational power and reliability. The design is relatively simple and needs very few rules. Two applications in which heat is transported by natural convection in confined and saturated media are studied: slender boxes heated from below (a kind of Bénard problem) and partially heated horizontal plates in rectangular domains (the Elder problem). The streamfunction and temperature patterns show that the results are coherent with those of other authors: steady state patterns and heat transfer depend both on the Rayleigh number and on the characteristic Darcy velocity derived from the values of the hydrological, thermal and geometrical parameters of the problems.The first author acknowledges the support of the Universidad Politécnica de Cartagena through a pre-doctoral scholarship and the economic support of the Universidad Católica del Norte to cover the costs to publish in open access

Stereoselective enzymatic reduction of 1,4-diaryl-1,4-diones to the corresponding diols employing alcohol dehydrogenases

Due to the steric hindrance of the starting prochiral ketones, the preparation of chiral 1,4-diaryl-1,4-diols through the asymmetric hydrogen transfer reaction has been mainly restricted to the use of metal-based catalysts, oxazaborolidines, or organocatalysts. Herein, we demonstrated the versatility of oxidoreductases, finding overexpressed alcohol dehydrogenase from Ralstonia sp. (E. coli/RasADH) as the most active and stereoselective biocatalyst. Thus, the preparation of a set of 1,4-diaryl-1,4-diols bearing different pattern substitutions in the aromatic ring was achieved with complete diastereo- and enantioselectivity under mild reaction conditions.Ministerio de Economía y Competitividad CTQ2016-75752-

Despoblación en Castilla y León

La despoblación es un tema en boga en la actualidad en el ámbito tanto nacional, como de la propia Castilla y León. En el presente documento analizaremos la evolución de la población de la comunidad a lo largo del último siglo, y veremos cómo esta sufre realmente un proceso de despoblación desde la década de los cincuenta que únicamente se ha revertido en los primero años de siglo XXI. Estudiaremos como la dispersión de las entidades municipales, sumado al devenir sectorial de la economía y la mala adaptación de la comunidad a esta, así como un saldo vegetativo deficitario desde hace décadas, han sido las principales causas de este fenómeno despoblador que ha sufrido Castilla y León. Por últimos estudiaremos las proyecciones de población realizadas por diferentes instituciones para la comunidad las cuales no auguran un futuro próspero en lo relativo a la demografía en la comunidad castellano-leonesa.Nowadays, depopulation its one of the most popular topics not only in Spain, also in Castille-Leon. The aim of the following essay is to study the population development in the comunnity over the last century, and we will prove that depopulation process, since the fifties, with only one exception, the first XXI century´s years. We will analyse how the municipalities dispersion, plus the economy develope and the negative vegetative growth have been the main reasons of this depopulation phenomenon. The last things we will study are the diferent population projection, been made for several institutions for Castille-Leon. Those one don´t suggest good news for the near future of the community population level.Departamento de Economía AplicadaGrado en Economí

Topological characterization of flow structures in resistive pressure-gradient-driven turbulence

9 pages, 13 figures.-- PACS nrs.: 52.35.Ra, 52.65.Kj, 47.27.−i.-- ArXiv pre-print available at: http://arxiv.org/abs/0811.3548Visualization of turbulent flows is a powerful tool to help understand the turbulence dynamics and induced transport. However, it does not provide a quantitative description of the observed structures. In this paper, an approach to characterize quantitatively the topology of the flows is given. The technique, which can be applied to any type of turbulence dynamics, is illustrated through the example of resistive ballooning instabilities.One of us (B.A.C.) is grateful to the Asociación EURATOM-CIEMAT for providing travel expenses. Part of this work is supported by the DGI (Dirección General de Investigación) of Spain under Project No. ENE2006-15244-C03-01 and by Grant No. CM-UC3M (Comunidad de Madrid—Universidad Carlos III) Project No. CCG07-UC3M/ESP-3407.Publicad

Multimodal feedback fusion of laser, image and temporal information

Trabajo presentado a la 8th International Conference on Distributed Smart Cameras (ICDSC) celebrada en Venecia (Italia) del 4 al 7 de noviembre de 2014.In the present paper, we propose a highly accurate and robust people detector, which works well under highly variant and uncertain conditions, such as occlusions, false positives and false detections. These adverse conditions, which initially motivated this research, occur when a robotic platform navigates in an urban environment, and although the scope is originally within the robotics field, the authors believe that our contributions can be extended to other fields. To this end, we propose a multimodal information fusion consisting of laser and monocular camera information. Laser information is modelled using a set of weak classifiers (Adaboost) to detect people. Camera information is processed by using HOG descriptors to classify person/non person based on a linear SVM. A multi-hypothesis tracker trails the position and velocity of each of the targets, providing temporal information to the fusion, allowing recovery of detections even when the laser segmentation fails. Experimental results show that our feedback-based system outperforms previous state-of-the-art methods in performance and accuracy, and that near real-time detection performance can be achieved.This work has been partially funded by the European project CargoANTs (FP7-SST-2013- 605598) and by the Spanish CICYT project DPI2013-42458-P.Peer Reviewe