Thread-spawning schemes for speculative multithreading

Speculative multithreading has been recently proposed to boost performance by means of exploiting thread-level parallelism in applications difficult to parallelize. The performance of these processors heavily depends on the partitioning policy used to split the program into threads. Previous work uses heuristics to spawn speculative threads based on easily-detectable program constructs such as loops or subroutines. In this work we propose a profile-based mechanism to divide programs into threads by searching for those parts of the code that have certain features that could benefit from potential thread-level parallelism. Our profile-based spawning scheme is evaluated on a Clustered Speculative Multithreaded Processor and results show large performance benefits. When the proposed spawning scheme is compared with traditional heuristics, we outperform them by almost 20%. When a realistic value predictor and a 8-cycle thread initialization penalty is considered, the performance difference between them is maintained. The speed-up over a single thread execution is higher than 5x for a 16-thread-unit processor and close to 2x for a 4-thread-unit processor.Peer ReviewedPostprint (published version

Income Inequality Rankings for Different Equivalence Scales and Population Health

This paper is divided in two parts. The first one is dedicated to analyse the inequality of the income distribution in Spain during the convergence process to the European Monetary Union. To carry out this task, we propose two robust models based on the quantile functions. Specifically, we use the Gamma and Beta quantile functions. The income inequality in Spain and the sensitivity of the results for different equivalence scales are analysed using the data corresponding to the first five waves (1994-1998) of the European Community Household Panel (ECHP). This survey contains data on individuals and households and the information is homogeneous across European countries. The second part of the paper is dedicated to study the correlation between income inequality and one of the most important health indicators such as life expectancy. We will try to add new perspectives to conventional studies of health inequalities. With this aim we will focus on relations between socio-economic factors and health of the individuals. In conclusion, this analysis seems to confirm the results obtained in previous researches. Income distribution has significant effects on health indicators. Although we can not confirm that the social capital is highly related with health, at least it is an important factor which helps to explain it. Key words: Inequality, social capital, health, European Community Household Panel

The spatial turn in history. Conceptual drifts and argentina´s historiographical racconto. Imagining located space segregation

El presente ensayo está orientado a demarcar herramientas para la construcción de una historia espacializada. A través de un examen de corrientes materialistas que focalizaron sus análisis en la cuestión espacial se demarcará conceptualmente el objeto de los espacios de segregación urbana. El énfasis está puesto en la concepción relacional del espacio y su carácter multiforme y dinámico. Además, se escrutarán algunas herramientas desarrolladas por la escuela de Chicago para pensar los universos de separación material y simbólica y las lógicas de desplazamiento como cualidad preeminente. Asimismo, el propósito de este ensayo es ofrecer una puesta a punto de la historiografía argentina en relación a la historio urbano-territorial y la necesidad de un giro espacial en los estudios de historia urbana localizada.The present essay is focused to score tools to build a spatialized history. Through an examination of materialistic currents focused their analysis on conceptually space issue in order to demarcate spaces of urban segregation. The emphasis is on the relational conception of space and its multifaceted and dynamic nature. Also, some tools developed by the Chicago School to think universes material and symbolic separation and logical shift shall be counted as a preeminent attribute. Also, the purpose of this essay is to offer a review on Argentina´s historiography in relation to urban-territorial topic and the need for a spatial turn in studies of localized urban history.Fil: Pascual, Cecilia María. Universidad Nacional de Rosario. Facultad de Humanidades y Artes. Centro de Estudios Culturales Urbanos; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentin

Hot carrier and hot phonon coupling during ultrafast relaxation of photoexcited electrons in graphene

We study, by means of a Monte Carlo simulator, the hot phonon effect on the relaxation dynamics in photoexcited graphene and its quantitative impact as compared to considering an equilibrium phonon distribution. Our multi-particle approach indicates that neglecting the hot phonon effect significantly underestimates the relaxation times in photoexcited graphene. The hot phonon effect is more important for a higher energy of the excitation pulse and photocarrier densities between $1$ and $3\times 10^{12} \mathrm{~cm}^{-2}$. Acoustic intervalley phonons play a non-negligible role, and emitted phonons with wavelengths limited up by a maximum (determined by the carrier concentration) induce a slower carrier cooling rate. Intrinsic phonon heating is damped in graphene on a substrate due to additional cooling pathways, with the hot phonon effect showing a strong inverse dependence with the carrier density.Comment: 12 pages, 5 figure

Theoretical study of the aerodynamics of delta wings

The present project emerges to provide a further development to the numerical an theoretical study on the aerodynamics of delta wings. The study is focused on the analysis of the rolling up of detached vortex sheets on the upper surface of a delta wing. First, the problem is introduced, describing the geometry used for the simulations. Then, the numerical approach is explained, giving details on the construction of the sheet of vortices that model the primary vortices that are created above the wing. In this section, the application of Kutta-Joukowski condition is explained. Also the procedure followed to build the vortices that roll up above the wing is detailed. Then, the results obtained, such as the variation of the pressure over the surface and the e ect of the thickness of the wing, are described and discussed. Finally, some limitations of the present study and further improvements are presented.Ingeniería Aeroespacia

The Sociolinguistic Integration of Immigrant Populations: Reflections on Its Study

Taking as its main point of departure the research carried out in the Madrid context by the Hispalin-UAH team of the IN.MIGRA2-CM project, the goal of this article is to reflect on the role of the linguistic dimension within the process of the social integration of migrant populations. It trains its sights on the need to work from a cognitive angle which may help to show how those involved in the process construct and re-define the new context, and on the need to consider the host population—as the prime conditioner of the process—and to identify and analyse in depth the components of identity that are modified as a result of cultural contact

Bases de datos en la enseñanza

A lo largo de este artículo se realizan algunas propuestas de enseñanza que tratan de responder a las demandas que actualmente reclama la sociedad a los centros educativos, en lo que se refiere a la actualización y tratamiento de la información ( su organización y acceso de forma rápida, sencilla y ordenada). Y se realiza desde el estudio y diseño de las posibilidades que ofrecen las actividades con y desde las bases de datos. Desde este planteamiento de eficacia y utilidad, se definen las bases de datos por su estructura y por los diferentes modos de organización de la información.Se realiza una exposición de los diferentes niveles de aplicación que poseen y qué posibles actividades se pueden realizar en cada uno de ellos (introducir datos, organizarlos, buscar información o manipular información, etc.). Así mismo se estudian los procesos cognitivos que se activan en el uso y tratamiento de las bases. Para todo ello, se marcan unos indicadores organizativos y metodológicos afines con la utilización de esta herramienta