Automation of Determination of Optimal Intra-Compute Node Parallelism

Maximizing the productivity of modern multicore and manycore chips requires optimizing parallelism at the compute node level. This is, however, a complex multi-step process. It is an iterative method requiring determining optimal degrees of parallel scalability and optimizing memory access behavior. Further, there are multiple cases to be considered, programs which use only MPI or OpenMP and hybrid (MPI +OpenMP) programs. This paper presents a set of three coordinated workflows for determining the optimal parallelism at the program level for MPI programs and at the loop level for hybrid (MPI+OpenMP) cases. The paper also details mostly automated implementations of these workflows using the PerfExpert infrastructure. Finally the paper presents case studies demonstrating both the applicability and the effectiveness of optimizing parallelism at the compute node level. The results shown in the paper will provide valuable information to further advance in the full automation of the workflows. The software implementing the parallelism scalability optimization is open source and available for download.Texas Advanced Computing Center (TACC)Computer Science

Repeatability and Two-Dimensionality of Model Scale Sloshing Impacts

Canonical test cases for sloshing wave impact problems are pre-sented and discussed. In these cases the experimental setup has been simpli?ed seeking the highest feasible repeatability; a rectangular tank subjected to harmonic roll motion has been the tested con?guration. Both lateral and roof impacts have been studied, since both cases are relevant in sloshing assessment and show speci?c dynamics. An analysis of the impact pressure of the ?rst four impact events is provided in all cases. It has been found that not in all cases a Gaussian ?tting of each individual peak is feasible. The tests have been conducted with both water and oil in order to obtain high and moderate Reynolds number data; the latter may be useful as simpler test cases to assess the capabilities of CFD codes in simulating sloshing impacts. The re-peatability of impact pressure values increases dramatically when using oil. In addition, a study of the two-dimensionality of the problem using a tank con?guration that can be adjusted to 4 di?erent thicknesses has been carried out. Though the kinemat-ics of the free surface does not change signi cantly in some of the cases, the impact pressure values of the ?rst impact events changes substantially from the small to the large aspect ratios thus meaning that attention has to be paid to this issue when reference data is used for validation of 2D and 3D CFD codes

How did the Sovereign debt crisis affect the Euro financial integration? A fractional cointegration approach.

This paper examines financial integration among stock markets in the Eurozone using the prices from each stock index. Monthly time series are constructed for four major stock indices for the period between 1998 and 2016. A fractional cointegrated vector autoregressive model is estimated at an international level. Our results show that there is a perfect and complete Euro financial integration. Considering the possible existence of structural breaks, this paper also examines the fractional cointegration within each regime, showing that Euro financial integration is very robust. However, in the financial and sovereign debt crisis regime, IBEX 35 appears to be the weak link in Euro financial integration, unless Euro financial integration recovers when this period ends

La ciudad ideal según fray Francesc Eiximenis y Rodrigo Sánchez de Arévalo.

Sin resume

Benefits of using a Wendland Kernel for free-surface flows

The aim of this paper Is lo discuss the influence of the selection of the interpolation kernel in the accuracy of the modeling of the internal viscous dissipation in Tree surface Hows, Simulations corresponding to a standing wave* for which an analytic solution available, are presented. Wendland and renormalized Gaussian kernels are considered. The differences in the flow pattern* and Internal dissipation mechanisms are documented for a range of Reynolds numbers. It is shown that the simulations with Wendland kernels replicate the dissipation mechanisms more accurately than those with a renormalized Gaussian kernel. Although some explanations are hinted we have Tailed to clarify which the core structural reasons for Mich differences are

Building domain specific languages upon the dbject constraint language (DCl)

The paper aim is to demonstrate how to extend oel, both with new data struetures and operations, in order to use it as a domain specific specification language. This data structures and operations are domain specific, and identified as a result of a domain analysis process. In conjunction with appropriate transformation techniques it will be possible togenerate code directly from system specifications.Eje: Ingeniería del software. Computación gráfica y visualizaciónRed de Universidades con Carreras en Informática (RedUNCI

Energy consumption in the US reconsidered. Evidence across sources and economic sectors

This study analyzes the impact of GDP shocks in USA on primary energy consumption and the reverse impact in a comprehensive and novel framework, distinguishing by economic sectors (commercial, industrial, residential and transportation) and energy source, i.e., total fossil (coal, natural gas and petroleum), nuclear, and renewable (hydroelectric, geothermal and biomass) for the period 1973:1 to 2015:2. To this end, we apply Granger causality analysis through the Hatemi-J [1] and Toda and Yamamoto [2] approaches from a time series perspective to evaluate the existence of asymmetries on this bidirectional relationship. The empirical results suggest that the impact of GDP on primary energy consumption is heterogeneous and energy source-specific, and an asymmetric behavior appears among cycles. Moreover, it seems clear that the US economy is highly dependent on petroleum energy consumption. The renewable energy sources do not seem to show any relationshipsources seem to show no relationship with economic growth, and finally, our results suggest that energy consumption in the industrial sector is key to economic growth and is also very sensitive to negative economic shocks

Spanish Research Report for 1992

7 páginas, 11 tablasPeer reviewe