Inertial waves in rapidly rotating flows: a dynamical systems perspective

An overview of recent developments in a wide variety of enclosed rapidly rotating flows is presented. Highlighted is the interplay between inertial waves, which have been predicted from linear inviscid considerations, and the viscous boundary layer dynamics which result from instabilities as the nonlinearities in the systems are increased. Further, even in the absence of boundary layer instabilities, nonlinearity in the system often leads to complicated interior flows due to subcritical instabilities, Eckhaus bands and heteroclinic dynamics. The ensuing spatio-temporally complex dynamics is analysed in terms of equivariant dynamical systems, providing a general perspective for the wide range of dynamics involved.Postprint (author's final draft

Modelling hydrological connectivity in burned areas. A case study from South of Spain

Overland flow connectivity depends on the spatio-temporal interactions of hydrological and geomorphic processes as well as on the human footprint on the landscape. This study deals with the modelling of hydrological connectivity in a burned area with different levels of fire severity. Namely, the objectives are to: i) characterize and ii) modelling the pre- (PreF) and post-fire (PostF) scenarios, as well as iii) evaluate the effect of the vegetation changes due to the fire and the initial post-fire management practices (construction of new skid trails and check-dams) on the magnitude and spatial pattern of connectivity. Four post-fire scenarios are simulated: immediately after the fire (PostF1), with new skids and without check-dams (PostF2), with new skids and check-dams and without vegetation recovery (PostF3), and with new skids and check-dams and incipient vegetation cover (PostF4). The study area corresponds to eleven headwater sub-catchments (total area of 329 ha) that cover the entire burned area of the mountain in the West and Southwest facing hillslopes (ca. 200 ha). This site is located in the province of Malaga, South of Spain, and all sub-catchments are disconnected between them. The fire started in 2014, 27 June and lasted two days. The landscape is mainly mountainous, with very steep slopes and marble rocks, Mediterranean climate, and a land use of shrubs and pine forests (pre-fire scenario). Settlements appear at the bottom of the slopes. After the wildfire, land management were carried out in order to remove completely the burned trees and thus new skid trails were built. Then, eleven concrete check-dams and twelve wooded check-dams were built in the main gullies. The different scenarios of linear landscape elements, vegetation cover and modifications on the topography related to the construction of new trails and check-dams were included in the simulations. The IC index of hydrological connectivity was chosen to perform this metric at a spatial resolution of 5 x 5 meters. The analysis of the different spatial patterns and temporal changes was done considering the different levels of fire severity and changes on hydrological connectivity were also analysed at the outlet of each sub-catchment.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech

Small aspect ratio Taylor-Couette flow: onset of a very-low-frequency three-torus state

The nonlinear dynamics of Taylor-Couette flow in a small aspect ratio annulus (where the length of the cylinders is half of the annular gap between them) is investigated by numerically solving the full three-dimensional Navier-Stokes equations. The system is invariant to arbitrary rotations about the annulus axis and to a reflection about the annulus half-height, so that the symmetry group is SO(2)×Z2. In this paper, we systematically investigate primary and subsequent bifurcations of the basic state, concentrating on a parameter regime where the basic state becomes unstable via Hopf bifurcations. We derive the four distinct cases for the symmetries of the bifurcated orbit, and numerically find two of these. In the parameter regime considered, we also locate the codimension-two double Hopf bifurcation where these two Hopf bifurcations coincide. Secondary Hopf bifurcations (Neimark-Sacker bifurcations), leading to modulated rotating waves, are subsequently found and a saddle-node-infinite-period bifurcation between a stable (node) and an unstable (saddle) modulated rotating wave is located, which gives rise to a very-low-frequency three-torus. This paper provides the computed example of such a state, along with a comprehensive bifurcation sequence leading to its onset.Postprint (published version

Lipid and Janus nanoparticles for active delivery

The following synthesis is based on the paper „Production of large quantities of „Janus“ nanoparticles using wax-in-water emulsions“ published by Ravaine et al.[1]In two beakers, 0.2 g of the synthesized silica particles were added to a solution of ethanol/water (6.7 % w/w, 100 mL), stirred and heated at 65 °C. To the suspensions were added 0.0220 g (Sample 1) or 0.0302 g (Sample 2) of cetyltrimethylammonium bromide (CTAB), respectively, and afterwards 6.682 g (for Sample 1) and 6.698 g (for Sample 2) of paraffin. After the paraffin was melted, the mixture was submitted to vigorous stirring by means of a homogenizer by 10000 rpm for 90 s. The emulsions were allowed to cool down to room temperature over night in order to get solid droplets of paraffin wax. For functionalization of the particles two solutions of 8 mL EtOH and NH4OH (7 % v/v) with 2.1 mL aminopropyltriethoxysilane (APTES) were prepared and added to both emulsions. After 12 h the solid wax droplets were filtrated, washed 3 times with ethanol, dissolved in DCM and heated till the wax was melted. The mixture was filtrated to receive the Janus particles as a white-beige powder (Samples 1 and 2).To prove the correctness of the procedure and as a result the existence of Janus particles, the particles, in a solution of 0.2 mL of water and ethanol (8:2), were mixed with 0.2 mL of a gold nanoparticle[2] (stabilized by citrate) suspension. The samples were analyzed by TEM. The synthesized silica particles exhibit a diameter of 100 nm, which can be seen in the following pictures (Fig. 1). It could be shown that the silica particles stayed in the water-phase in the DCM-water dual-phase-system, which shows that the synthesized particles are hydrophilic and not hydrophobic. It can be seen that in both samples (Samples 1 and 2, Fig. 2) the gold particles were bound to the functionalized silica particles, whereas sample 2 looks like a Janus particle (Fig. 2, right side). Unfortunately, in both cases the distribution of the gold particles is not very homogeneous and dense like it could be shown in the literature.[1], [2] Because the TEM samples were not completely dry, water can be seen in form of shadows around the particles.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech

Obra nueva antigua e inscripción en el registro de la propiedad: régimen jurídico, especialidades de la normativa urbanística andaluza y doctrina de la dirección general de los registros y del notariado

This piece of work focuses on the study of the registration qualification of new building declarations about old construction statement, based on the competence of the state law regulations to determine the necessary requirements for public documentation and registration of them, without prejudice to the reference to the regional law regulations to verify the prescription of any urban infraction in which they could be incur. To do this I will focus on the presentation of its legal regimefrom 1990 to the present time, taking into account the doctrine in this regard emanated from the Dirección General de los Registros y del Notariado

El procés de despoblament a les comarques de la Cerdanya i l'Alt Urgell

Des de mitjan segle passat les comarques de muntanya catalanes han sofert un lent però ininterromput degoteig d'habitants, i actualment la situació és de profunda crisi geografica causada per aquesta forta regressió. En aquest article es descriu la dinamica de la població a les comarques pirinenques catalanes de la Cerdanya i l'Alt Urgell, bo i centrant-se en el conjunt de pobles abandonats o en perill de ser-ho com a situació extrema d'un procés generalitzat. Es fa una aproximació a les causes d'abandonament dels pobles amb un tractament específic sobre el medi físic com a subjecte agent i pacient alhora.Desde mediados del siglo pasado las comarcas de montaña catalanas han sufrido una lenta pero ininterrumpida pérdida de habitantes, y actualmente la situación es de profunda crisis demográfica causada por esta fuerte regresión. En el presente articulo se describe la dinámica de la población en las comarcas catalanas de la Cerdaña y el Alto Urgel, centrándose en el conjunto de pueblos abandonados o en peligro de serlo como situación extrema de un proceso generalizado. Se hace una aproximación a las causas de abandono de los pueblos con un tratamiento especifico sobre el medio fisico como sujeto agente y paciente a la vez.Depuis la première moitié du siècle dernier, les pays (comarques) de montaigne en Catalogne ont connu une perdue de population lente mais continue. La situation actuelle est marqué par une profonde crise démographique i cause de cette forte régression. Dans cet article, on décrit la dynamique de la population des pays catalans de Cerdanya et l'Alt Urgell, particdikrement celle de l'ensemble des villages abandonnées ou en cours de dépeuplement, comrne la situation extrème d'un processus généralisé. On fait aussi référence aux causes de l'abandon, en donant un traitement spécifique à l'environement physique considéré A la fois comme élement actif et passif.The catalan mountain counties are experiencing a steady decrase of popdation since the middle of last century, and the current situation is characterised by a deep demographical crisis. This article explains the dynamics of population in the Catalan Pyrenees counties of La Cerdanya and Alt Urgell, and particularly the abandoned villages with as an extreme situation of a global process. There is an attempt to explain the causes of the abandonment of villages with a special consideration of the physical environment as an active and passive agent of depopulation

Ressenyes

Index de les obres ressenyades: N. MYERS, El atlas Gaia de la gestión del planeta. N. MIDDELETON, Atlas of world issues. N. MIDDELETON, Atlas of environmental issues. G. LEAN ; D. HINRICHSEN ; A. MARKHAM, Atlas of the environmen

La detención de menores extranjeros no acompañados en el marco de la Unión Europea y del Consejo de Europa

Programa Consolider "El tiempo de los derechos" (HURI-AGE

Modelos numérico y analítico para el diseño de laminados compuestos híbridos con capacidad de falla gradual bajo cargas de flexión

El presente trabajo describe el estudio reciente de los laminados de materiales compuestos híbridos sujetos a cargas de flexión, para luego usar este conocimiento en la creación de herramientas analíticas y numéricas que asisten el diseño de laminados híbridos con capacidad de falla gradual en un ensayo de flexión a cuatro puntos. Estas herramientas son inicialmente verificadas usando datos experimentales de laminados en los cuales se logró obtener falla gradual, pero la naturaleza de la falla y los mecanismos por los cuales se da, requieren un mayor entendimiento. El modelo en el cual se basa la herramienta analítica consiste en una adaptación de la solución analítica para ensayos de flexión a cuatro puntos en el cual el material es sometido a grandes deformaciones en combinación con la teoría clásica de laminados y mecánica de la fractura. Por otra parte, el modelo numérico utiliza elementos cohesivos para modelar tanto el daño intralaminar como el interlaminar, usando las propiedades de la resina para definir el comportamiento cohesivo interlaminar y usando una distribución de resistencias intralaminares según el modelo estadístico de Weibull. Una vez verificados los modelos, estos son usados para diseñar nuevos laminados híbridos optimizados, que reducen la cantidad de láminas ultradelgadas y por lo tanto, el número total de láminas requeridas para un mismo espesor, esto a su vez implica una posible reducción en el costo de fabricación y el tiempo de manufactura. Además, un laminado estándar (laminado no hibridado) es fabricado con fines comparativos; los ensayos en estos nuevos laminados validan la capacidad predictiva de ambas herramientas en casos falla gradual y falla repentina, tanto en laminados híbridos como estándar; y demuestran que es posible conseguir laminados híbridos con capacidad de falla gradual a un menor costo.The present work describes the recent studies on hybrid composite laminates under bending loads; then, this knowledge is used to create analytical and numerical tools that assist the design of hybrid layups which can fail gradually in a four-point bending test. These tools are initially verified using experimental data from layups where such a gradual failure was achieved, but the nature of the failure process and failure mechanisms need additional study. The analytical tool is based on modifications from the analytical solution of large deflections of a beam in a four-point bending test together with the classical laminate and fracture mechanics theories. On the other hand, the numerical model is set using cohesive elements to model intralaminar as well as interlaminar damage, where the interlaminar strength is based on resin properties and the intralaminar strength is set based on Weibull statistical distribution. Once the models were verified, they are used to design new optimised hybrid layups that reduce the number of thin-plies required and therefore, the total amount of plies required for the same layup thickness; these imply a potential decrease in the cost of the layup and the time to be manufactured. One non-hybrid layup was also manufactured for baseline comparison, testing results on all these new layups exhibited the expected failure sequence and failure mechanisms; validating the accuracy of the tools to predict brittle and gradual failure in hybrid and standard composites; besides, it shows that it is possible to obtain hybrid layups with gradual failure capabilities using other configurations.Royal Academy of EngineeringNovel Hybrid Composites to improve structural performance of a Compact Electric Utility Vehicles ChassisLínea de Investigación: Modelamiento de falla en materiales compuestos híbridosMaestrí