Nos estamos jugando un modelo de agricultura y alimentación

Los transgénicos, las políticas agrarias que benefician a unos pocos, el control de las grandes multinacionales o la desregulación de los mercados son, junto a otras muchas cuestiones, un ataque a la agricultura social a pequeña escala y a una manera de entender nuestra alimentación. Pedimos la opinión de la organización agraria que, posicionada a favor de la Soberanía Alimentaria, denuncia que la recién aprobada 'Ley de representatividad del sector agrario' es también un nuevo ataque a dicho modelo campesino

Phase only transmit beamforming for spectrum sharing microwave systems

This paper deals with the problem of phase-only transmit beamforming in spectrum sharing microwave systems. In contrast to sub-6 GHz schemes, general microwave systems require a large number of antennas due to its huge path loss. As a consequence, digital beamforming needs a large number of computational resources compared to analog beamforming, which only needs a single radio-frequency chain, results the less computational demanding solution. Analog schemes are usually composed by a phase shifter network whose elements transmit at a certain fixed power so that the system designer shall compute the phase values for each element given a set of directions. This approach leads to non-convex quadratic problems where the traditional semidefinite relaxation fails to deliver satisfactory outcomes. In order to solve this, we propose a nonsmooth method that behaves well in several scenarios. Numerical evaluations in different spectrum sharing scenarios, which show the performance of our method, are provided.Peer ReviewedPostprint (author's final draft

Los terratenientes frente al cambio agrario, 1940-1954

El impacto del cambio agrario de posguerra sobre la economía y la sociedad españolas ha sido un tema recurrente en la investigación histórica. Sin embargo, la posición de los grandes propietarios rústicos ante dicho cambio, principalmente el hecho de si pudieron establecer una estrategia para maximizar los beneficios, sigue siendo una cuestión abierta a debate. Como una aportación a este campo, presento un estudio de los grandes terratenientes residentes en Madrid en la posguerra. La principal fuente sobre la que se basa el trabajo son las declaraciones de la contribución sobre la renta, una fuente fiscal apenas explorada que permite conocer la economía privada de los grandes contribuyentes. El estudio se ha centrado en definir quiénes eran los grandes propietarios, las características de sus dominios rústicos, las estrategias de conservación del patrimonio y su relación con el resto de sectores económicos. Posteriormente, a partir de un análisis diacrónico, expongo la difícil adaptación que protagonizó la aristocracia terrateniente, fruto de la imposibilidad de mantener la estructura tradicional del rentismo agrario. Finalmente se analiza el ascenso de una nueva clase de terratenientes, que se diferenciaban notablemente del resto de las élites de la capital.Historical research has frequently examined the impact of postwar agrarian changes on the economy and society of Spain. However, there is still much debate regarding the role of large‐scale landowners in relation to these changes. This paper offers a contribution to this debate by examining the owners of large estates living in Madrid during this period. An examination of the individual income tax returns of the highest income tax bracket is a historical source that has hardly been tapped and offers a picture of their private economy. This study focuses on identifying large‐scale landowners, the characteristics of their estates, their strategies of property conservation and their relationship with other economic sectors. We also present a diachronic study that exposes the difficult adaptation landed aristocracy faced at a time when it was impossible to maintain their traditional agrarian rentier economy. Finally, this article examines the rise of a new class of landowners that were clearly differentiated from the Madrid elites

EF4, EF4-M and EF4-Ł: A companion to BN4 and two modal four-valued systems without strong Łukasiewicz-type modal paradoxes

The logic BN4 was defined by R.T. Brady as a four-valued extension of Routley and Meyer’s basic logic B. The system EF4 is defined as a companion to BN4 to represent the four-valued system of (relevant) implication. The system Ł was defined by J. Łukasiewicz and it is a four-valued modal logic that validates what is known as strong Łukasiewicz-type modal paradoxes. The systems EF4-M and EF4-Ł are defined as alternatives to Ł without modal paradoxes. This paper aims to define a Belnap-Dunn semantics for EF4, EF4-M and EF4-Ł. It is shown that EF4, EF4-M and EF4-Ł are strongly sound and complete w.r.t. their respective semantics and that EF4-M and EF4-Ł are free from strong Łukasiewicz-type modal paradoxes

Estratigrafía secuencial de sistemas deltaicos en cuencas de antepais: ejemplos de Sant Llorenç de Munt, Montserrat y Roda (paleógeno, cuenca de antepaís surpirenaica)

After the sedimentological study of the Sant Llorenc del Munt, Montserrat and Roda deltaic systems, a stratigraphic subdivision based on three different scale transgressiveregressive sequences has been developed. This subdivision has been established on the coastal facies belts from the deduced shoreline (and associated facies belts) migration.These transgressive-regressive sequences are formed by a lower transgressive part with a deepening-upwards trend and a retrogradational staclung pattern and an upper regressive part, with shallowing-upwards trend and a progradational stacking pattern. The lowest scale sequences (metrical) have been named "fundamental sequences". A series of "composite sequences", intermediate scale (decametric to hectometric), have been defined afier the study of the staclung pattem of the fundamental sequences. After the study of the stacking pattem of composite sequences there have been defined a series of large-scale (decametric to kilometric) "composite megasequences".A sequential subdivision based on non interpretative models (which does not imply the recognition of a controlling factor or set of factors) can be effective. However, to reach some predictive results is necessary to estimate (qualitative and quantitatively) the greater nurnber of controlling pararneters on the cyclicityAfter the analysis of the field examples, there hasbeen demonstrated that there are three main controlling factors of the cyclicity (eustacy, subsidence and sediment supply) worlung in a combined way. In foreland basins the rates of action of the non-global controlling factors (subsidence and sediment supply) are variable in time and space. That variability makes sequences local for correlation purposes. Sequences will only be correlatable for those areas where the controlling-parameters have operated with a similar magnitude and a similar periodicity. Most of the changes on controlling parameters have not a determined periodicity, so, the resulting sequences will not either have a determined periodicity (or duration)

Modelado en dinámica de fluidos computacional (CFD) de transporte de masa en materiales porosos

La difusión y la adsorción son fenómenos complejos que ocurren durante las reacciones catalíticas de forma acoplada y en función del tiempo. Estos procesos pueden ser estudiados mediante un análisis microcinético. Un método para realizar este análisis es el uso de un aparato de Respuesta por Frecuencia (FR). El objetivo de este proyecto es la creación de un modelo, utilizando el software de simulación COMSOL Multiphysics, que recree un experimento FR en el que un gas es comprimido y expandido periódicamente para favorecer la difusión y adsorción en un material poroso. Diferentes variables han de tenerse en cuenta, centrándose este proyecto en la simulación del material poroso – el catalizador – y los procesos de transporte de masa, además del correcto cálculo de campos de presión y velocidad, y transferencia de calor. Finalmente, se presenta un estudio de los resultados de la evolución del experimento, obtenidos del modelo computacional final.Departamento de Ingeniería Energética y FluidomecánicaGrado en Ingeniería Mecánic