Diseño e implementación de un jammer configurable en FPGA

[ES] Este trabajo fin de máster consiste en la realización de un prototipo de un sistema jammer. Estos sistemas tienen como función la transmisión de señales de radiofrecuencia para crear una interferencia intencionada con el objetivo de interrumpir o perturbar una comunicación por radiofrecuencia. Siendo el objetivo principal de este proyecto la interferencia de comunicaciones que empleen una modulación de salto en frecuencia, teniendo la posibilidad de modificar los parámetros del sistema para ajustarse dinámicamente a cada situación. Para esto, el sistema a desarrollar está basado en FPGA, la cual se encargará de la generación de la interferencia adaptada a cada estado. Además, será necesaria la integración de la FPGA junto con el microprocesador, así como el test de las diferentes partes que integran el sistema.Martínez Cuesta, A. (2020). Diseño e implementación de un jammer configurable en FPGA. Universitat Politècnica de València. http://hdl.handle.net/10251/136750TFG

Ecocinismos. El medio ambiente natural y humano bajo la linterna cínica

[ES] Esta tesis doctoral parte de la semejanza entre las recomendaciones de la ética ecológica y de las antiguas éticas helenísticas, para analizar los principales problemas ecosociales de nuestro tiempo bajo la mirada del cinismo griego. El objetivo del autor en este trabajo es, desde una lectura libre, recuperar algunas de las divisas del cinismo griego (vivir conforme a la naturaleza, invalidar la moneda en curso, cosmopolitismo y parresía) para paliar la actual crisis ecológica. La metodología utilizada está en sintonía con la línea hermenéutica de la "fusión de horizontes" de Gadamer, tratando de ofrecer una interpretación dinámica de la tradición que posibilite comprender mejor el presente. Este trabajo consta de dos partes con tres capítulos cada una: En la primera parte se trata de recuperar un elenco de herramientas críticas del cinismo antiguo, para su posterior aplicación en la segunda parte. Se comienza con un paralelismo entre Helenismo y sociedad contemporánea en base a unos rasgos fisonómicos comunes como épocas de crisis. Continúa con una presentación de los principales representantes y características del cinismo griego. Concluye con un recorrido histórico de la recepción del cinismo desde el Renacimiento a la Posmodernidad. En la segunda parte se aplica ese instrumental cínico a la crítica ecológica contemporánea aplicando los conceptos "quinismo" y "cinismo"de Sloterdijk. Comienza con un examen de la visión humana acerca del animal, proponiendo sustituir el tradicional humanismo de dominancia por un humanismo de pertenencia. Continúa aplicando la divisa cínica -Invalidar la moneda en curso-con una serie de propuestas para reconciliar economía y ecología, derribando el mito del crecimiento económico ilimitado. Concluye examinando el discurso hipócrita (cínico en el actual sentido de la palabra) en el ámbito político y publicitario

Ancient cynicism as a therapy for the crisis of global capitalism

Although a temporal distance of more than two thousands of years, Hellenism and contemporary society show analogous “spirits of time” (zeitgeist); with characteristics such as cultural malaise, loss of the old political and social frameworks, cultural syncretism, or recovery of nature and regulatory framework. Hellenistic ethics emerged as therapeutics that would guide the individual in this crisis of the Greek world. In this paper examines the possibility of using the critical tools of the old cynicism, to apply them therapeutically on the global ecological crisis, created by industrial capitalism. The principles of ancient cynicism can be recycled for a project of degrowth societyA pesar de una distancia temporal de más de dos milenios, el Helenismo y la sociedad contemporánea, muestran “espíritus de época” análogos;  con rasgos como malestar cultural, pérdida de los antiguos marcos políticos y sociales, sincretismo cultural, o recuperación de la naturaleza como marco normativo. Las éticas helenísticas surgieron como terapéuticas que orientasen al individuo en esta situación de crisis del mundo griego. En este artículo se examina la posibilidad de aprovechar las herramientas críticas del cinismo antiguo, para aplicarlas terapéuticamente a la crisis ecológica global, generada por el capitalismo industrial. Los principios del cinismo antiguo pueden ser reciclables y reutilizables para un proyecto de sociedad decrecentista

Is single layer graphene a promising anode for sodium-ion batteries?

In an attempt to find an adequate carbon material to achieve a successful reversible adsorption of Na+ ions, single layer graphene, is experimentally investigated in this work, for the first time, as anode for sodium-ion batteries. To this end, single layer graphene that was grown on copper foil by chemical vapor deposition was subjected to extended galvanostatic cycling and to cyclic voltammetry in the potential range of 0-2.8 V versus Na/Na+. Regardless of the current density and electrolyte formulation used, the amount of Na+ ions adsorbed/desorbed reversibly per surface area (specific reversible cell capacity) was very modest and comparable to that obtained with bare copper electrodes of reference, thus suggesting that the reversible capacity of the single layer graphene electrode is mostly due to the electrochemical response of the copper substrate. These experimental results clearly agree with recent theoretical calculations showing that the adsorption of Na+ ions on the surface of single layer graphene is energetically unfavourable unless that surface includes significant defects density.Financial support from IBERDROLA FOUNDATION (www.fundacioniberdrola.org, Projects 2014-2015) and the Spanish Ministry of Economy and Competitiveness MINECO (under Projects ENE2011-28318-CO-02 and ENE2014-52189-C2-2-R) is gratefully acknowledged. A. Ramos and N. Cuesta, respectively, thank the Spanish Research Council for Scientific Research (CSIC) for a JAE-Doc contract, co-funded by the European Social Fund (ESF), and the Spanish Ministry of Economy and Competitiveness (MINECO) for a pre-doctoral grant (BES-2012-052711).Peer reviewe

Theoretical study on molten alkali carbonate interfaces

The properties and structure of relevant interfaces involving molten alkali carbonates are studied using molecular dynamics simulation. Lithium carbonate and the Li/Na/K carbonate eutectic mixture are considered. Gas phases composed of pure CO2 or a model flue gas mixture are analyzed. Similarly, the adsorption of these gas phases on graphene are studied, showing competitive CO2 and N2 adsorption that develops liquid-like layers and damped oscillation behavior for density. The interaction of the studied carbonates with graphene is also characterized by development of adsorption layers through strong graphene–carbonate interactions and the development of hexagonal lattice arrangements, especially for lithium carbonate. The development of molten salts–vacuum interfaces is also considered, analyzing the ionic rearrangement in the interfacial region. The behavior of the selected gas phases on top of molten alkyl carbonate is also studied, showing the preferential adsorption of CO2 molecules when flue gases are considered.European Union’s H2020- MSCA-RISE-2016-CO2MPRISE-73487

Insights into carbon nanotubes and fullerenes in molten alkali carbonates

The properties of single-walled carbon nanotubes and carbon fullerenes in molten alkali carbonates (MACs) were studied as a function of the considered nanomaterial and the ions into the molten salt using classical molecular dynamics simulations. The adsorption and confinement in carbon nanotubes is developed by efficient interaction of carbonate ions in the inner and outer walls of the nanotubes whereas alkali cations do not show a remarkable interaction with the nanomaterial. Analogous solvation mechanisms are inferred for carbon fullerenes with large disruption of the liquid structuring of MAC at high fullerene concentrations. The solvation ability of the studied lithium–sodium–potassium carbonate eutectic mixture for both types of nanomaterials is essential for considering this fluid in the development of composite materials for advanced technological applications.European Union H2020- MSCA-RISE-2016-CO2MPRISE-73487

Increasing the effectiveness of directory caches by avoiding the tracking of noncoherent memory blocks

© 2013 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other uses, in any current or future media, including reprinting/republishing this material for advertising or promotional purposes, creating new collective works, for resale or redistribution to servers or lists, or reuse of any copyrighted component of this work in other works.A key aspect in the design of efficient multiprocessor systems is the cache coherence protocol. Although directory-based protocols constitute the most scalable approach, the limited size of the directory caches together with the growing size of systems may cause frequent evictions and, consequently, the invalidation of cached blocks, which jeopardizes system performance. Directory caches keep track of every memory block stored in processor caches in order to provide coherent access to the shared memory. However, a significant fraction of the cached memory blocks do not require coherence maintenance (even in parallel applications) because they are either accessed by just one processor or they are never modified. In this paper, we propose to deactivate the coherence protocol for those blocks that do not require coherence. This deactivation means directory caches do not have to keep track of noncoherent blocks, which reduces directory cache occupancy and increases its effectiveness. Since the detection of noncoherent blocks is carried out by the operating system, our proposal only requires minor hardware modifications. Simulation results show that, thanks to our proposal, directory caches can avoid the tracking of about 66 percent (on average) of the blocks accessed by a wide range of applications, thereby improving the efficiency of directory caches. This contributes either to shortening the runtime of parallel applications by 15 percent (on average) while keeping directory cache size or to maintaining performance while using directory caches 16 times smaller.This work was supported by the Spanish MICINN, Consolider Programme and Plan E funds, as well as European Commission FEDER funds, under Grants CSD2006-00046 and TIN2009-14475-C04-01. It was also partly supported by (PROMETEO from Generalitat Valenciana (GVA) under Grant ROMETEO/2008/060). B. Cuesta was with Universitat Politecnica de Valencia while working on this paper.Cuesta Sáez, BA.; Ros Bardisa, A.; Gómez Requena, ME.; Robles Martínez, A.; Duato Marín, JF. (2013). Increasing the effectiveness of directory caches by avoiding the tracking of noncoherent memory blocks. IEEE Transactions on Computers. 62(3):482-495. https://doi.org/10.1109/TC.2011.241S48249562

Temporal-Aware Mechanism to Detect Private Data in Chip Multiprocessors

© 2013 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other uses, in any current or future media, including reprinting/republishing this material for advertising or promotional purposes, creating new collective works, for resale or redistribution to servers or lists, or reuse of any copyrighted component of this work in other works.Most of the data referenced by sequential and parallel applications running in current chip multiprocessors are referenced by only one thread and can be considered as private data. A lot of recent proposals leverage this observation to improve many aspects of chip multiprocessors, such as reducing coherence overhead or the access latency to distributed caches. The effectiveness of those proposals depend to a large extent on the amount of detected private data. However, the mechanisms proposed so far do not consider thread migration and the private use of data within different application phases. As a result, a considerable amount of data is not detected as private. In order to make this detection more accurate and reaching more significant improvements, we propose a mechanism that is able to account for both thread migration and private data within application phases. Simulation results for 16-core systems show that, thanks to our mechanism, the average number of pages detected as private significantly increases from 43% in previous proposals up to 74% in ours. Finally, when our detection mechanism is used to deactivate the coherence for private data in a directory protocol, our proposal improves execution time by 13% with respect to previous proposals.This work was supported by the Spanish MINECO, as well as European Commission FEDER funds, under grant TIN2012-38341-C04-01/03 and by the VIRTICAL project (grant agreement no 288574) which is funded by the European Commission within the Research Programme FP7.Ros Bardisa, A.; Cuesta Sáez, BA.; Gómez Requena, ME.; Robles Martínez, A.; Duato Marín, JF. (2013). Temporal-Aware Mechanism to Detect Private Data in Chip Multiprocessors. En Proceedings of the International Conference on Parallel Processing. IEEE. 562-571. https://doi.org/10.1109/ICPP.2013.70S56257

Gender Differences in Cooperation: Experimental Evidence on High School Students

Charles Darwin (1874) stated that women are less selfish but men are more competitive. Very recent papers (Eckel & Grossman, 1998, 2001 or Andreoni and Vesterlund 2001, among others) have shown the relevance of gender in altruism in both ultimatum and dictator games. In this paper we analyze the role of gender in repeated Prisoners' Dilemma played by Spanish high-school students in both a square lattice and a heterogeneous network. We find that female students have a higher probability of cooperation than male students