Turbulent fluctuations above the buffer layer of wall-bounded flows

The behaviour of the velocity and pressure fluctuations in the logarithmic and outer layers of turbulent flows is analysed using spectral information and probability density functions from channel simulations at Reτ _2000. Comparisons are made with experimental data at higher Reynolds numbers. It is found, in agreement with previous investigations, that the intensity profiles of the streamwise and spanwise velocity components have logarithmic ranges that are traced to the widening spectral range of scales as the wall is approached. The same is true for the pressure, both theoretically and observationally, but not for the normal velocity or for the tangential stress cospectrum, although even those two quantities have structures with lengths of the order of several hundred times the wall distance. Because the logarithmic range grows longer as the Reynolds number increases, variables which are ‘attached’ in this sense scale in the buffer layer in mixed units. These results give strong support to the attached-eddy scenario proposed by Townsend (1976), but they are not linked to any particular eddy model. The scaling of the outer modes is also examined. The intensity of the streamwise velocity at fixed y/h increases with the Reynolds number. This is traced to the large-scale modes, and to an increased intensity of the ejections but not of the sweeps. Several differences are found between the outer structures of different flows. The outer modes of the spanwise and wall-normal velocities in boundary layers are stronger than in internal flows, and their streamwise velocities penetrate closer to the wall. As a consequence, their logarithmic layers are thinner, and some of their logarithmic slopes are different. The channel statistics are available electronically at http://torroja.dmt.upm.es/ftp/channels/

Learning STRIPS Action Models with Classical Planning

This paper presents a novel approach for learning STRIPS action models from examples that compiles this inductive learning task into a classical planning task. Interestingly, the compilation approach is flexible to different amounts of available input knowledge; the learning examples can range from a set of plans (with their corresponding initial and final states) to just a pair of initial and final states (no intermediate action or state is given). Moreover, the compilation accepts partially specified action models and it can be used to validate whether the observation of a plan execution follows a given STRIPS action model, even if this model is not fully specified.Comment: 8+1 pages, 4 figures, 6 table

Coupled mantle dripping and lateral dragging controlling the lithosphere structure of the NW-Moroccan margin and the Atlas Mountains: A numerical experiment

Recent studies integrating gravity, geoid, surface heat flow, elevation and seismic data indicate a prominent lithospheric mantle thickening beneath the NW-Moroccan margin (LAB >200 km-depth) followed by thinning beneath the Atlas Domain (LAB about 80 km-depth). Such unusual configuration has been explained by the combination of mantle underthrusting due to oblique Africa-Eurasia convergence together with viscous dripping fed by asymmetric lateral mantle dragging, requiring a strong crust-mantle decoupling. In the present work we examine the physical conditions under which the proposed asymmetric mantle drip and drag mechanism can reproduce this lithospheric configuration. We also analyse the influence of varying the kinematic boundary conditions as well as the mantle viscosity and the initial lithosphere geometry. Results indicate that the proposed drip-drag mechanism is dynamically feasible and only requires a lateral variation of the lithospheric strength. The further evolution of the gravitational instability can become either in convective removal of the lithospheric mantle, mantle delamination, or subduction initiation. The model reproduces the main trends of the present-day lithospheric geometry across the NW-Moroccan margin and the Atlas Mountains, the characteristic time of the observed vertical movements, the amplitude and rates of uplift in the Atlas Mountains and offers an explanation to the Miocene to Pliocene volcanism. An abnormal constant tectonic subsidence rate in the margin is predicted. (C) 2013 Elsevier B.V. All rights reserved.Peer ReviewedPostprint (author's final draft

Reynolds number effects on the Reynolds-stress budgets in turbulent channels

Budgets for the nonzero components of the Reynolds-stress tensor are presented for numerical channels with Reynolds numbers in the range Reτ ≤180–2000. The scaling of the different terms is discussed, both above and within the buffer and viscous layers. Above (x_2^+)≈150, most budget components scale reasonably well with u_t^3/h, but the scaling with (u_t^4)/v is generally poor below that level. That is especially true for the dissipations and for the pressure-related terms. The former is traced to the effect of the wall-parallel large-scale motions, and the latter to the scaling of the pressure itself. It is also found that the pressure terms scale better near the wall when they are not separated into their diffusion and deviatoric components, but mostly only because the two terms tend to cancel each other in the viscous sublayer. The budgets, together with their statistical uncertainties, are available electronically from http://torroja.dmt.upm.es/channels

El original de la loa "Pariendo juró Pelaya", recogida en la "Octava Parte"

El presente trabajo estudia y edita el original de la loa "Pariendo juró Pelaya", recogida en la Octava parte de las comedias de Lope de Vega. El original, firmado y melior, ha sido hallado en una colección de poemas custodiada por la Hispanic Society of America de Nueva York.The original of the loa "Pariendo juró Pelaya", collected in the Octava parte of Lope de Vega's comedies, is studied and edited. The original, autographed and melior, has been recently found in a compilation of poetry kept at the Hispanic Society of America

La profesionalización en las artes: próximidad al mito

Este trabajo indaga la relación y circunstancias de las artes y su enlace profesional con el presente modelo de sociedades. En este sentido, el sistema económico-político, el aspecto global del concepto Arte, y una atmósfera de disolución de ideologías y valores, han determinado una paradójica mezcla de relatividad y graves contradicciones; este hecho produce una realidad incompatible para el colectivo artístico y su inserciónen el resto de la comunidadThis work inquires te relationship and circumstances of the arts and its professional link, with the present pattern of societies. On this sense, the economic-politic system, the global aspect of concept Art, and a dissolution’s atmosphere of ideologies and values, have determined a paradoxical mixture of relativity and serious contradictions; that produced an incompatible reality for te artistic collective and its insertion in te rest ofcommunit

Analysis of post-tensioned structures by means of a constitutive serial-parallel rule of mixtures

The main purpose is to test a reliable method based on a three-dimensional (3D) finite-element (FE) model to simulate the constitutive behavior of reinforced concrete structures strengthened with post-tensioned tendons. Large scale 3D FE models will be used, where the nonlinear material behavior and geometrical analysis based on incremental iterative load methods will be adopted

Educación y Rebelión: Arte Acción Colectiva como Recurso Didáctico

La realidad social y política debe ser tratada como una materia global en cualquier sistema educativo. La Educación de las Artes Visuales como experiencia colectiva fuera de las aulas, implementa fuertemente las conexiones entre docente y alumnos, valores éticos y ciudadanía.The social and political reality must be treated as a global matter any educational system. The Visual Arts Education and collective experience outside the classroom, implements strong connections between teachers and students, ethical values and citizenshi

José Julio Martín Romero, La guerra en la literatura castellanadel siglo XV, Londres, Department of Iberian and Latin American Studies...

José Julio Martín Romero, La guerra en la literatura castellanadel siglo XV, Londres, Department of Iberian and Latin American Studies, Queen Mary, University of London (‘Papers of the Medieval Hispanic Research Seminar’, 23), 2015, 121 pp