Corrosión y Mantenimiento en la Naútica de Recreo

Programa Retos de Conferencias del Centro Nacional de Investigaciones Metalúrgicas (CENIM).CSICLa corrosión en el medio marino es un problema que lleva afectando al sector naval desde sus orígenes. Multitud de embarcaciones sufren diariamente las consecuencias de este fenómeno tan difícil de detener. No son pocos los barcos que se han hundido debido a la pérdida de los pernos de la quilla o a la desaparición de un grifo de fondo con problemas de corrosión. En la presente charla, se pretende dar una visión general de los problemas más habituales encontrados en el sector náutico, analizando sus causas y proponiendo diferentes soluciones para prevenir, minimizar e incluso eliminar sus efectos. Se expondrán algunos casos reales y se mostraran nuevas propuestas para evitar estos problemas. Así mismo, se mostraran los resultados del estudio de dispositivos antiincrustación por ultrasonidos realizados durante los últimos meses en varios puntos de la costa española.N

GPGPU-Enabled Physics Based Deformed Model Simulation

Computer simulation techniques are widely adopted nowadays in many areas like manufacturing, engineering, graphics, animation, virtual reality and so on. However, the standard finite element based simulation is notorious for its expensive computation. To address this challenge, I present a GPU-based parallel implementation for simulating large elastic deformation. Classic modal analysis provides a set of orthonormal bases vectors, which span a spectral space encoding the dynamics of the elastic body. As each basis vector is orthogonal to each other, the computation is completely decoupled and can be well-fit into the modern GPGPU platform. We further explore the latest feature of NVIDIA CUDA so that the result of GPU computation can be directly used for upcoming rendering/visualization and a significant amount of overheads for transmitting data from client GPU and host CPU via the PCI-Express bus are avoided. Real-time simulation is made possible with this technique for many cases that otherwise is not possible

Different Performance of Factors Affecting the Estimation of the Corrosion Rate in Magnesium Alloys by Implementation of the Common Methods for Electrochemical Measurements

financial support for this work from the Ministry of Science and Innovation of Spain (MAT 2009-13530)Peer reviewe

On the mass assembly of low-mass galaxies in hydrodynamical simulations of structure formation

Cosmological hydrodynamical simulations are studied in order to analyse generic trends for the stellar, baryonic and halo mass assembly of low-mass galaxies (M_* < 3 x 10^10 M_sun) as a function of their present halo mass, in the context of the Lambda-CDM scenario and common subgrid physics schemes. We obtain that smaller galaxies exhibit higher specific star formation rates and higher gas fractions. Although these trends are in rough agreement with observations, the absolute values of these quantities tend to be lower than observed ones since z~2. The simulated galaxy stellar mass fraction increases with halo mass, consistently with semi-empirical inferences. However, the predicted correlation between them shows negligible variations up to high z, while these inferences seem to indicate some evolution. The hot gas mass in z=0 halos is higher than the central galaxy mass by a factor of ~1-1.5 and this factor increases up to ~5-7 at z~2 for the smallest galaxies. The stellar, baryonic and halo evolutionary tracks of simulated galaxies show that smaller galaxies tend to delay their baryonic and stellar mass assembly with respect to the halo one. The Supernova feedback treatment included in this model plays a key role on this behaviour albeit the trend is still weaker than the one inferred from observations. At z>2, the overall properties of simulated galaxies are not in large disagreement with those derived from observations.Comment: 19 pages, 12 figures. Accepted for publication in MNRAS: 6th August 2013. First submitted: 7th July 201

Plan de negocios del proyecto inmobiliario

This document comprehends Mirablau’s business plan. A housing proposal in height, the tallest and most significant building in Manta, one of the most developed cities in Ecuador today. We report all relevant information for planning and implementing the project, from a comprehensive analysis of Macroeconomic environment of the country to the financial feasibility and specification of the processes necessary for proper management. The paper concludes that it is a feasible project, meeting all of required returns by promoters as well as pointing out the sensitive areas and their potential impact.Este documento comprende el plan de negocios para el proyecto inmobiliario Miralblau. Una propuesta de vivienda en altura, el edificio más alto y significativo de Manta, una de las ciudades de mayor desarrollo en la actualidad ecuatoriana. Se documenta toda la información relevante para la planificación y ejecución del proyecto, desde un análisis completo del entorno Macroeconómico del país, hasta la factibilidad financiera y la especificación de los procesos necesarios para su adecuada gerencia. El documento concluye que Miralblau es un proyecto factible cumpliendo con los rendimientos requeridos por los promotores además de puntualizar las áreas sensibles y sus posibles repercusiones

Multi-scale accretion in dense cloud cores and the delayed formation of massive stars

The formation mechanism of massive stars remains one of the main open problems in astrophysics, in particular the relationship between the mass of the most massive stars, and that of the cores in which they form. Numerical simulations of the formation and evolution of large molecular clouds, within which dense cores and stars form self-consistently, show in general that the cores' masses increase in time, and also that the most massive stars tend to appear later (by a few to several Myr) than lower-mass stars. Here we present an idealized model that incorporates accretion onto the cores as well as onto the stars, in which the core's mass growth is regulated by a ``gravitational choking'' mechanism that does not involve any form of support. This process is of purely gravitational origin, and causes some of the mass accreted onto the core to stagnate there, rather than being transferred to the central stars. Thus, the simultaneous mass growth of the core and of the stellar mass can be computed. In addition, we estimate the mass of the most massive allowed star before its photoionizing radiation is capable of overcoming the accretion flow onto the core. This model constitutes a proof-of-concept for the simultaneous growth of the gas reservoir and the stellar mass, the delay in the formation of massive stars observed in cloud-scale numerical simulations, the need for massive, dense cores in order to form massive stars, and the observed correlation between the mass of the most massive star and the mass of the cluster it resides in. Also, our model implies that by the time massive stars begin to form in a core, a number of low-mass stars are expected to have already formed.Comment: Submitted to MNRAS. Originally submitted to Nature Astronomy, but withdrawn from that journal after not having received a reviewer's report for over four months. Comments welcom