Internal framework and geochemistry of the Carboniferous Huaco granite pluton, Sierra de Velasco, NW Argentina

The A-type Huaco granite pluton of the Velasco range (Sierras Pampeanas of northwest Argentina) is formed by three coeval granitic facies and contains subordinate coeval-to-late facies, as well as enclaves, dikes and stocks that show different temporal relations, textures and compositions. The dominant facies (Regional Porphyritic Granite; RPG) is a porphyritic two-mica monzo- to syenogranite, with abundant microcline megacrysts up to 12 cm in size. It was emplaced in a dominant extensional setting and has a mainly crustal source but with participation of a mantle-derived component. The RPG transitions towards two coeval and co-genetic granite facies, at its margins (Border Granite; BG) and around Be-pegmatites (Adjacent Porphyritic Granite; APG). These two facies have a finer-grained texture and smaller and less abundant megacrysts. They are also monzo- to syenogranites, but a slight decrease in the biotite/muscovite ratio is observed from the BG to the RPG to the APG. Trace element modeling suggests that the RPG, BG and APG differentiated from the same magma source by fractional crystallization. Temporally older mafic (ME) and felsic (FE) enclaves are common in the pluton. The ME can be considered partially assimilated remnants of a mafic component in the genesis of the RPG, whereas the FE seem to be remnants of premature aplites. Other subordinate rocks intrude the RPG and are, hence, temporally younger: felsic dikes (FD), dioritic dikes (DD) and equiganular granites (EqG) are clearly posterior, whereas coeval-to-late Be-pegmatites (BeP) and orbicular granites (OG) formed during the final stages of crystallization of the pluton. The BeP, OG and FD indicate the presence of abundant water and volatiles. The EqG form small stocks that intrude the RPG and were possibly originated from purely crustal sources. The DD probably correspond to a younger unrelated episode of mafic magmatism.Fil: Sardi, Fernando Guillermo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto Superior de Correlación Geológica. Universidad Nacional de Tucumán. Facultad de Ciencias Naturales e Instituto Miguel Lillo. Departamento de Geología. Cátedra Geología Estructural. Instituto Superior de Correlación Geológica; ArgentinaFil: Grosse, Pablo. Fundación Miguel Lillo. Dirección de Geología. Instituto de Minerología y Petrografia; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán; ArgentinaFil: Murata, Mamoru. Naruto University; JapónFil: Lozano Fernández, Rafael Pablo. Instituto Geológico y Minero de España; Españ

Nonlinear Time-Domain Structure/Aerodynamics Coupling in Systems with Concentrated Structural Nonlinearities

This paper details a practical approach for predicting the aeroelastic response (structure/aerodynamics coupling) of flexible pod/missile-type configurations with freeplay/hysteresis concentrated structural nonlinearities. The nonlinear aeroelastic response of systems in the presence of these nonlinearities has been previously studied by different authors; this paper compiles methodologies and related airworthiness regulations. The aeroelastic equations of the pod/missile configuration are formulated in state-space form and time-domain integrated with Fortran/Matlab codes developed ad hoc for dealing with freeplay/hysteresis nonlinearities. Results show that structural nonlinearities change the classical aeroelastic behaviour with appearence of non-damped motion (LCOs and chaotic motion)

Suppressors of selection

Inspired by recent works on evolutionary graph theory, an area of growing interest in mathematical and computational biology, we present the first known examples of undirected structures acting as suppressors of selection for any fitness value $r > 1$. This means that the average fixation probability of an advantageous mutant or invader individual placed at some node is strictly less than that of this individual placed in a well-mixed population. This leads the way to study more robust structures less prone to invasion, contrary to what happens with the amplifiers of selection where the fixation probability is increased on average for advantageous invader individuals. A few families of amplifiers are known, although some effort was required to prove it. Here, we use computer aided techniques to find an exact analytical expression of the fixation probability for some graphs of small order (equal to $6$, $8$ and $10$) proving that selection is effectively reduced for $r > 1$. Some numerical experiments using Monte Carlo methods are also performed for larger graphs.Comment: New title, improved presentation, and further examples. Supporting Information is also include

Procedural tree mesh generator plugin for Blender

Treball final de Grau en Disseny i Desenvolupament de Videojocs. Codi: VJ1241. Curs acadèmic: 2020/2021The goal of this End-of-Degree project has been to create a useful tool that works on a procedural way in order to create unique vegetation tree models that adapts to the needs of each user. In the last decade, procedural and modular generation techniques have seen their use increased notably in the video game industry. These techniques allow the creation of different instances of almost every element that compose a game in an automatic way, making it possible to achieve single unique gameplay experiences for the users with less time spent by developers. Blender creation suite has been used for the development of the project. This work has two main parts: the procedural generation system of the optimized tree models and an integration of user input through an user interface added in Blender. On one side, the generation of the trees has been divided into four parts: generation of the roots, trunk, branches and leaves. On the other side, would be the interaction of the distinct user inputs parameters within the procedural scripted behavior allowing the user to control the final output. Finally, a fully working tree model generator plugin with a random behaviour driven by user inputs with the indicated characteristics in the Project Design Document has been acquired (see Chapter 2)

Study and analysis of state-of-the-art FCS-MPC strategies for thermal regulation of power converters

La degradación en los convertidores de potencia basados en silicio, enmarcados en sistemas de tracción eléctrica y fuentes de energías renovables, es un tema de estudio de especial interés para aquellas aplicaciones donde los fallos amenazan la seguridad de personas o donde el mantenimiento es particularmente costoso. Motivado por la influencia de los fallos en IGBTs sobre los fallos habituales en los convertidores de potencia comunes, este trabajo utiliza la herramienta software PLECS como marco de trabajo para la simulación de algoritmos de control predictivo basado en modelo con conjunto finito de acciones de control (FCS-MPC) que pretenden -simultáneamente a conseguir el seguimiento eléctrico- extender directa o indirectamente la vida útil de los IGBTs. El trabajo se enfoca principalmente a la simulación en ordenador de los algoritmos controlando un inversor de dos niveles conectado a una carga RL. Además, pretende también introducir la implementación de éstos sobre un microcontrolador para su estudio controlando el inversor simulado en la plataforma PLECS RT Box 1, con el fin último de poder desarrollar validaciones de los controladores basadas en técnicas Hardware-In-the-Loop.Degradation of silicon-based power electronics converters in traction and renewable energy systems is a topic of interest particularly where module failure supposes a safety threat or where maintenance becomes especially expensive. Motivated by the influence of IGBT aging in usual power converters, this work uses the software tool PLECS as framework to simulate Finite Control Set Model Predictive Control (FCSMPC) algorithms that, simultaneously to achieving a certain current tracking, aim to directly or indirectly extend IGBTs’ lifetime. Whilst the work focuses on offline simulation of the algorithms on PLECS, it also targets to pave the way to implement algorithms in a micro-controller and to study how they control a two-level inverter connected to a RL load simulated on a PLECS RT Box 1 platform. The ultimate goal is to develop validations based on Hardware-In-the-Loop techniques of the control algorithms.Universidad de Sevilla. Máster Universitario en Ingeniería Electrónica, Robótica y Automátic

Multiscale modelling of CO2 hydrogenation reactions on Ni-based catalysts

Programa de Doctorat en Química Teòrica i Modelització Computacional[eng] Global warming and climate change, mostly due to the increasing concentration of greenhouse gases in the atmosphere, are producing devastating effects. Among the different greenhouse gases, CO2 is one of the major contributors. It is expected that, as a consequence of the ever increasing industry based on fossil fuels burning, the atmospheric amounts of CO2 will still rise in the following decades. In that sense, several research groups have focused on different strategies to mitigate the CO2 atmospheric concentration. Among the different possibilities, an interesting strategy is CO2 valorization, which reduce the environmental impact related with carbon dioxide and, at the same time, generate new value-added chemicals, thus offering an economic incentive to CO2 mitigation. In this regard, Ni-based catalysts have emerged as promising catalysts due to their relatively high activity at low cost. The aim of the present doctoral thesis is to study the CO2 hydrogenation reaction for different well-defined models of Ni-based catalysts through a theoretical multiscale approach. First, we have studied the complete CO2 hydrogenation reaction over the extended Ni(111) surface and we have found that this surface produces CO rather than methane. We suggest that the experimental observations of methane are not because of the Ni(111) itself but rather because of other active Ni facets, the cooperation between different facets, the support effect or the interfacial sites lying in between the metal and the support. We have also studied the reverse water-gas shift reaction on a Ni/TiC model system. After a careful inspection of the structural, electronic, magnetic and catalytic properties of different Nin supported clusters we have chosen a Ni4 cluster supported on TiC(001) as a model system for a deeper study. Based on kinetic Monte Carlo simulations, we have unveiled the boost of catalytic activity experimentally observed for the Ni/TiC system with respect to the clean TiC(001) surface, which we attributed to a synergic effect between the supported Ni cluster ant the TiC substrate in such a way that H is produced at the supported Ni cluster that further spillover to the TiC surface, where the hydrogenation reactions occur. Interestingly, coverage effects reveal a mismatch on the activity predictions from the density functional theory calculations and the kinetic Monte Carlo results. Finally, we have studied in detail the CO2 hydrogenation reaction on a Ni4 cluster supported on CeO2(111). We have found that there is a synergic effect between the two three-fold hollow sites of the Ni cluster, which defines the catalytic activity and selectivity. Moreover, we have shown the important role of the inclusion of some Eley- Rideal reactions on the final mechanism, activity and selectivity.[cat] L’augment dels gasos d’efecte hivernacle a l’atmosfera està produint efectes devastadors en el medi ambient, sent el CO2 un dels gasos que mes hi contribueix. Per això, diferents grups de recerca s’han centrat en buscar estratègies per reduir les concentracions de CO2 atmosfèric. Una de les estratègies és la conversió de CO2 en altres vectors energètics. En aquest sentit, els catalitzadors basats en níquel son àmpliament utilitzats degut al seu baix cost econòmic i alta capacitat catalítica. L’objectiu d’aquesta tesi doctoral és l’estudi de la reacció d’hidrogenació de CO2 en diferents models de catalitzadors basats en níquel mitjançant una aproximació teòrica multiescala. En primer lloc, hem estudiat la reacció d’hidrogenació de CO2 en la superfície de Ni(111) i hem vist que aquesta superfície produeix CO en lloc de metà, en desacord amb els resultats experimentals on majoritàriament s’observa metà. En base als nostres resultats suggerim que la formació de metà és deguda a altres superfícies de níquel, a l’efecte cooperatiu entre les diferents superfícies de níquel presents en les nanopartícules o per efectes del suport o la interfase entre el metall i el suport. En segon lloc, hem estudiat la conversió de CO2 a CO en un sistema model format per un clúster de níquel suportat sobre carbur de titani (Ni/TiC). Després d’un anàlisi detallat de diferents propietats hem escollit un clúster de Ni4 suportat sobre TiC(001) com a model per estudiar la reacció de conversió de CO2 a CO. Les nostres simulacions manifesten un augment de l’activitat catalític pel sistema de Ni/TiC en relació a la superfície de TiC(001), tal i com s’observa experimentalment. Aquest augment de l’activitat és degut a un efecte sinèrgic entre el clúster de Ni i la superfície de TiC. Finalment, hem estudiat la reacció d’hidrogenació de CO2 en un clúster de Ni4 suportat sobre la superfície de CeO2(111). Les nostres simulacions mostren un efecte sinèrgic entre els diferents llocs d’adsorció del clúster de níquel que defineixen l’activitat catalítica i la selectivitat. Per últim, hem observat el rol d’algunes reaccions de tipus Eley-Rideal pel que fa al mecanisme, l’activitat i la selectivitat del catalitzador