Achieving High Speed CFD simulations: Optimization, Parallelization, and FPGA Acceleration for the unstructured DLR TAU Code

Today, large scale parallel simulations are fundamental tools to handle complex problems. The number of processors in current computation platforms has been recently increased and therefore it is necessary to optimize the application performance and to enhance the scalability of massively-parallel systems. In addition, new heterogeneous architectures, combining conventional processors with specific hardware, like FPGAs, to accelerate the most time consuming functions are considered as a strong alternative to boost the performance. In this paper, the performance of the DLR TAU code is analyzed and optimized. The improvement of the code efficiency is addressed through three key activities: Optimization, parallelization and hardware acceleration. At first, a profiling analysis of the most time-consuming processes of the Reynolds Averaged Navier Stokes flow solver on a three-dimensional unstructured mesh is performed. Then, a study of the code scalability with new partitioning algorithms are tested to show the most suitable partitioning algorithms for the selected applications. Finally, a feasibility study on the application of FPGAs and GPUs for the hardware acceleration of CFD simulations is presented

Aggregation of predictors for nonstationary sub-linear processes and online adaptive forecasting of time varying autoregressive processes

In this work, we study the problem of aggregating a finite number of predictors for nonstationary sub-linear processes. We provide oracle inequalities relying essentially on three ingredients: (1) a uniform bound of the $\ell^1$ norm of the time varying sub-linear coefficients, (2) a Lipschitz assumption on the predictors and (3) moment conditions on the noise appearing in the linear representation. Two kinds of aggregations are considered giving rise to different moment conditions on the noise and more or less sharp oracle inequalities. We apply this approach for deriving an adaptive predictor for locally stationary time varying autoregressive (TVAR) processes. It is obtained by aggregating a finite number of well chosen predictors, each of them enjoying an optimal minimax convergence rate under specific smoothness conditions on the TVAR coefficients. We show that the obtained aggregated predictor achieves a minimax rate while adapting to the unknown smoothness. To prove this result, a lower bound is established for the minimax rate of the prediction risk for the TVAR process. Numerical experiments complete this study. An important feature of this approach is that the aggregated predictor can be computed recursively and is thus applicable in an online prediction context.Comment: Published at http://dx.doi.org/10.1214/15-AOS1345 in the Annals of Statistics (http://www.imstat.org/aos/) by the Institute of Mathematical Statistics (http://www.imstat.org

Phylodynamics of H5N1 Highly Pathogenic Avian Influenza in Europe, 2005-2010: Potential for Molecular Surveillance of New Outbreaks.

Previous Bayesian phylogeographic studies of H5N1 highly pathogenic avian influenza viruses (HPAIVs) explored the origin and spread of the epidemic from China into Russia, indicating that HPAIV circulated in Russia prior to its detection there in 2005. In this study, we extend this research to explore the evolution and spread of HPAIV within Europe during the 2005-2010 epidemic, using all available sequences of the hemagglutinin (HA) and neuraminidase (NA) gene regions that were collected in Europe and Russia during the outbreak. We use discrete-trait phylodynamic models within a Bayesian statistical framework to explore the evolution of HPAIV. Our results indicate that the genetic diversity and effective population size of HPAIV peaked between mid-2005 and early 2006, followed by drastic decline in 2007, which coincides with the end of the epidemic in Europe. Our results also suggest that domestic birds were the most likely source of the spread of the virus from Russia into Europe. Additionally, estimates of viral dispersal routes indicate that Russia, Romania, and Germany were key epicenters of these outbreaks. Our study quantifies the dynamics of a major European HPAIV pandemic and substantiates the ability of phylodynamic models to improve molecular surveillance of novel AIVs

Implementation And Verification Of A Lunar Mission Subsystems (II)

El presente trabajo final de carrera consiste en implementar y verificar algunos de los subsistemas que forman la misión Lunar diseñada por el equipo Team FREDNET con motivo del Google Lunar X Prize. Uno de los proyectistas se encargará de los subsistemas del Rover Lunar y el otro se encargará de los subsistemas del Lunar Lander. Debido a que hay multiples subsistemas es posible que haya un tercer proyectista. Este proyecto se realiza en colaboración con otros investigadores de múltiples nacionalidades por lo que requiere formar parte del grupo en un proyecto real de exploración lunar. Este proyecto incluye habilidades de trabajo en equipo, preparación de resultados, toma de decisiones, etc. REQUISITOS: - Estar terminando la carrera técnica de Sistemas, Telemática o Aeronáutica (Obligatorio) - Disponibilidad horaria y presencial (Obligatorio) - Tener conocimientos en buses y radio-enlaces (Deseable) - Manejo de sistema operativo WINDOWS y LINUX (Deseable

TO SWITCH OR NOT TO SWITCH: THE EFFECTS OF INVITING BILINGUAL LATINOS TO SWITCH LANGUAGES IN PSYCHOTHERAPY

The effects of inviting bilingual Latinos to switch languages in psychotherapy were examined, as was the question of whether cultural identity affected how this offer was perceived. Fifty-two bilingual Latino university students listened to one of two recordings of a psychotherapy session with a bilingual Latina therapist and client. In one recording, the therapist invited the client to switch to Spanish; in the other, she did not invite the client to switch. Participants were then asked to imagine themselves in the client's role and rate the therapist's credibility and multicultural competence, the alliance they would anticipate, and their willingness to see the therapist. Results showed that when the therapist invited the client to switch, she received higher multicultural competence ratings. Also, participants high in ethnic identity commitment rated this therapist as being less credible. These findings could contribute to the bilingual psychotherapy literature and have implications for practice and research

¿Por qué es difícil exigir derechos culturales?

Portal de Noticias en InternetEl artículo analiza el tema de los derechos culturales en términos de su conocimiento, apropiación y dificultades para su implementación por parte de la ciudadanía. Hace un breve recuento de la situación actual en el Distrito Federal, en términos de la información con la que cuenta la comisión de derechos humanos.Al Momento Noticia

Notas sobre La vegetación de Andalucía. II

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