Evolución de los computadores: Textos para una exposición

En el texto, de carácter divulgativo, se presentan algunos sistemas que fueron un hito en la evolución histórica de los computadores, desde los primeros artefactos mecánicos de cálculo, hasta los recientes supercomputadores. Ordenados cronológicamente, se comentan piezas de hardware, procesadores y otros dispositivos escogidos por su relevancia, y se incluyen algunas características técnicas y comentarios que los ubican históricamente, y que permiten relacionarlos y comprender su importancia dentro de un contexto tecnológico

Integrability, Supersymmetry and Coherent States. A volume in honour of Professor Véronique Hussin

ISBN 978-3-030-20087-

Plataforma de test para paneles fotovoltaicos aeroespaciales

Este trabajo describe el diseño de un sistema de potencia eléctrica (EPS) para realizar test de laboratorio que permitirán mejorar el diseño de una EPS para un satélite CubeSat operando en órbitas LEO. El proyecto comprende el diseño de la PCB y del software para una placa Arduino Mega, que actúa de interfaz entre la EPS y un computador o un microcontrolador externo. El software incluye funciones de acceso a bajo nivel para obtención de medidas y control de la EPS durante las pruebas de laboratorio que simulen distintas condiciones de captación y consumo de energía eléctrica.This work describes the design of an electrical power system (EPS) to perform laboratory tests that will improve the design of an EPS for a CubeSat satellite operating in LEO orbits. The project includes the design of the PCB and the software for an Arduino Mega board, which acts as interface between the EPS and a computer or an external microcontroller. The software includes low-level access functions to get measurements and EPS control during laboratory tests that simulate different conditions of production and consumption of electrical energy.Proyecto Fin de Carrera de la Univ. de Granada. Departamento de Electrónica y Tecnología de Computadores.GranaSAT: Grupo Electrónica Aeroespacia

Partial coherent states in graphene

Producción CientíficaWe employ a symmetric gauge to describe the interaction of electrons in graphene with a magnetic field which is orthogonal to the layer surface and to build the so-called partial and bidimensional coherent states for this system in the Barut-Girardello sense. We also evaluate the corresponding probability and current densities as well as the mean energy value.Junta de Castilla y León (projects VA137G18 and BU229P18)Ministerio de Economía, Industria y Competitividad (project MTM2014-57129-C2-1-P

Exact results for nonequilibrium dynamics in Wigner phase space

We study time evolution of Wigner function of an initially interacting one-dimensional quantum gas following the switch-off of the interactions. For the scenario where at t=0the interactions are suddenly suppressed, we derive a relationship between the dynamical Wigner function and its initial value. A two-particle system initially interacting through two different interactions of Dirac delta type is examined. For a system of particles that is suddenly let to move ballistically (without interactions) in a harmonic trap in d dimensions, and using time evolution of one-body density matrix, we derive a relationship between the time dependent Wigner function and its initial value. Using the inverse Wigner transform we obtain, for an initially harmonically trapped noninteracting particles in ddimensions, the scaling law satisfied by the density matrix at time tafter a sudden change of the trapping frequency. Finally, the effects of interactions are analyzed in the dynamical Wigner function.Ministerio de Economía, Industria y Competitividad (grant MTM2014-57129-C2-1-P)Junta de Castilla y León (grants BU229P18, VA057U16, and VA137G18

Jurassic Fe-Mn macro-oncoids from pelagic swells of the External Subbetic (Spain) : evidences of microbial origin

Ferromanganesiferous macro-oncoids are distinctive from the External Subbetic Zone (Betic Cordillera, SE Spain) in relation to a major heterochronic unconformity, with a Middle Bathonian-Lower Oxfordian minimum hiatos and a Lowest Bathonian-Lowest Kimmeridgian maximum hiatus. The Fe-Mn macro-oncoids (43 mm mean-size) consist of microbial laminae with planar and arborescent to dendrolitic morphologies. Under petrographic microscopy, the planar morphologies are made up by condensed fibrillar meshworks whereas the dendrolitic ones are similar to Frutexites. Alternation between these two types of laminae reveals a rhythmic growth in the Fe-Mn macro-oncoids. Bacterial and fungal filaments are observed in SEM analyses as microbial mats constituted by a disperse web of filaments exhibiting a branching tube-like morphology with diameters ranging between 2 and 10 µm. Aggregates of coccoid-shaped forms are also registered by SEM analyses. Taxonomical approximation of the microbiota is complex, though in the thin section the condensed fibrillar meshworks look like cyanobacteria, and in SEM images the morphology of the filaments resembles fungal hyphae and green algae, whereas coccoids are assigned to cyanobacteria. The precipitation of Fe-Mn is related to the chemoorganotrophic behaviour of the benthic microbial communities, probably corresponding to the fungal mats and other chemosynthetic microbes. Inorganic precipitation mechanisms are regarded as insufficient for the accumulation of a significant amount of MnO. An efficient precipitation of Mn from natural water largely depended on the presence of Mn-oxidizing microorganisms. Sediment-starved zones of pelagic swells of the External Subbetic, located in the deep euphotic zone, were the best places for microbially mediated authigenesis

Minimalismo continuo en las creaciones musicales Ámbitos 7 y 8 para cuarteto de cuerdas

Muestro en primer lugar aspectos generales del minimalismo musical estadounidense, sus representantes principales, sus recursos discontinuos y la manera de utilizarlos. En segundo lugar una síntesis de mi método de intervalos para la creación musical: en qué consiste, cuáles fueron los trabajos teóricos y prácticos que impulsaron a idearlo y qué creaciones he hecho. Finalmente mis cuartetos de cuerdas Ámbitos 7 para dos violines y dos violas (2019) y Ámbitos 8 para dos violines, viola y violonchelo (2019), donde convergen el minimalismo y dicho método. En ambas creaciones hay sonidos continuos, proporcionando un minimalismo no de puntos, sino de ondas