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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
Regional productivity variation and the impact of public capital stock: an analysis with spatial interaction, with reference to Spain
In this paper we examine whether variations in the level of public capital across Spain?s Provinces affected productivity levels over the period 1996-2005. The analysis is motivated by contemporary urban economics theory, involving a production function for the competitive sector of the economy („industry?) which includes the level of composite services derived from 'service' firms under monopolistic competition. The outcome is potentially increasing returns to scale resulting from pecuniary externalities deriving from internal increasing returns in the monopolistic competition sector. We extend the production function by also making (log) labour efficiency a function of (log) total public capital stock and (log) human capital stock, leading to a simple and empirically tractable reduced form linking productivity level to density of employment, human capital and public capital stock. The model is further extended to include technological externalities or spillovers across provinces. Using panel data methodology, we find significant elasticities for total capital stock and for human capital stock, and a significant impact for employment density. The finding that the effect of public capital is significantly different from zero, indicating that it has a direct effect even after controlling for employment density, is contrary to some of the earlier research findings which leave the question of the impact of public capital unresolved.Public capital, urban economics, spatial econometrics.
Reforma Fiscal y Bienestar: El Caso de Chile
Welfare-maximizing fiscal structures are determined in a two-sector model of endogenous growth calibrated for the Chilean economy. Under the baseline, the current tax structure is found to be close to the optimal one. The result that the tax on physical cFiscal policy, endogenous growth, welfare
Analysing the impact of public capital stock using the NEG wage equation: a panel data approach
This paper examines the relationship between the level of public infrastructure and the level of productivity using panel data for the Spanish provinces over the period 1984-2004, a period which is particularly relevant due to the substantial changes occurring in the Spanish economy at that time. The underlying model used for the data analysis is based on the wage equation, which is one of a handful of simultaneous equations which when satisfied correspond to the short-run equilibrium of New Economic Geography theory. This is estimated using a spatial panel model with fixed time and province effects, so that unmodelled space and time constant sources of heterogeneity are eliminated. The model assumes that productivity depends on the level of educational attainment and the public capital stock endowment of each province. The results show that although changes in productivity are positively associated with changes in public investment within the same province, there is a negative relationship between productivity changes and changes in public investment in other regions.spatial economics, public infrastructure, productivity, panel data, economic geography
Lactic Acid Bacteria and Yeast Inocula Modulate the Volatile Profile of Spanish-Style Green Table Olive Fermentations
In this work, Manzanilla Spanish-style green table olive fermentations were inoculated
with Lactobacillus pentosus LPG1, Lactobacillus pentosus Lp13, Lactobacillus plantarum Lpl15, the yeast
Wickerhanomyces anomalus Y12 and a mixed culture of all them. After fermentation (65 days),
their volatile profiles in brines were determined by gas chromatography-mass spectrometry analysis.
A total of 131 volatile compounds were found, but only 71 showed statistical differences between
at least, two fermentation processes. The major chemical groups were alcohols (32), ketones (14),
aldehydes (nine), and volatile phenols (nine). Results showed that inoculation with Lactobacillus
strains, especially L. pentosus Lp13, reduced the formation of volatile compounds. On the contrary,
inoculation with W. anomalus Y12 increased their concentrations with respect to the spontaneous
process, mainly of 1-butanol, 2-phenylethyl acetate, ethanol, and 2-methyl-1-butanol. Furthermore,
biplot and biclustering analyses segregated fermentations inoculated with Lp13 and Y12 from the
rest of the processes. The use of sequential lactic acid bacteria and yeasts inocula, or their mixture,
in Spanish-style green table olive fermentation could be advisable practice for producing differentiated
and high-quality products with improved aromatic profile.Gobierno de España-OliFilm-AGL-2013-48300-
Flabase: towards the creation of a flamenco music knowledge base
Online information about flamenco music is scattered overdifferent sites and knowledge bases. Unfortunately, thereis no common repository that indexes all these data. Inthis work, information related to flamenco music is gath-ered from general knowledge bases (e.g., Wikipedia, DB-pedia), music encyclopedias (e.g., MusicBrainz), and spe-cialized flamenco websites, and is then integrated into anew knowledge base called FlaBase. As resources fromdifferent data sources do not share common identifiers, aprocess of pair-wise entity resolution has been performed.FlaBase contains information about 1,174 artists, 76pa-los(flamenco genres), 2,913 albums, 14,078 tracks, and771 Andalusian locations. It is freely available in RDF andJSON formats. In addition, a method for entity recognitionand disambiguation for FlaBase has been created. The sys-tem can recognize and disambiguate FlaBase entity refer-ences in Spanish texts with an f-measure value of 0.77. Weapplied it to biographical texts present in Flabase. By usingthe extracted information, the knowledge base is populatedwith relevant information and a semantic graph is createdconnecting the entities of FlaBase. Artists relevance is thencomputed over the graph and evaluated according to a fla-menco expert criteria. Accuracy of results shows a highdegree of quality and completeness of the knowledge base
Teaching telecommunication standards: bridging the gap between theory and practice
©2017 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.Telecommunication standards have become a reliable mechanism to strengthen collaboration between industry and research institutions to accelerate the evolution of communications systems. Standards are needed to enable cooperation while promoting competition. Within the framework of a standard, the companies involved in the standardization process contribute and agree on appropriate technical specifications to ensure diversity and compatibility, and facilitate worldwide commercial deployment and evolution. Those parts of the system that can create competitive advantages are intentionally left open in the specifications. Such specifications are extensive, complex, and minimalistic. This makes telecommunication standards education a difficult endeavor, but it is much demanded by industry and governments to spur economic growth. This article describes a methodology for teaching wireless communications standards. We define our methodology around six learning stages that assimilate the standardization process and identify key learning objectives for each. Enabled by software-defined radio technology, we describe a practical learning environment that facilitates developing many of the needed technical and soft skills without the inherent difficulty and cost associated with radio frequency components and regulation. Using only open source software and commercial of-the-shelf computers, this environment is portable and can easily be recreated at other educational institutions and adapted to their educational needs and constraints. We discuss our and our students' experiences when employing the proposed methodology to 4G LTE standard education at Barcelona Tech.Peer ReviewedPostprint (author's final draft
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