12,454 research outputs found

    The extended minimal geometric deformation of SU(NN) dark glueball condensates

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    The extended minimal geometric deformation (EMGD) procedure, in the holographic membrane paradigm, is employed to model stellar distributions that arise upon self-interacting scalar glueball dark matter condensation. Such scalar glueballs are SU(NN) Yang-Mills hidden sectors beyond the Standard Model. Then, corrections to the gravitational wave radiation, emitted by SU(NN) EMGD dark glueball stars mergers, are derived, and their respective spectra are studied in the EMGD framework, due to a phenomenological brane tension with finite value. The bulk Weyl fluid that drives the EMGD is then proposed to be experimentally detected by enhanced windows at the eLISA and LIGO.Comment: 9 pages, 7 figure

    Extended quantum portrait of MGD black holes and information entropy

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    The extended minimal geometric deformation (EMGD) is employed on the fluid membrane paradigm, to describe compact stellar objects as Bose--Einstein condensates (BEC) consisting of gravitons. The black hole quantum portrait, besides deriving a preciser phenomenological bound for the fluid brane tension, is then scrutinized from the point of view of the configurational entropy. It yields a range for the critical density of the EMGD BEC, whose configurational entropy has global minima suggesting the configurational stability of the EMGD BEC.Comment: 9 pages, 7 figures, matches the published versio

    cudaBayesreg: Parallel Implementation of a Bayesian Multilevel Model for fMRI Data Analysis

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    Graphic processing units (GPUs) are rapidly gaining maturity as powerful general parallel computing devices. A key feature in the development of modern GPUs has been the advancement of the programming model and programming tools. Compute Unified Device Architecture (CUDA) is a software platform for massively parallel high-performance computing on Nvidia many-core GPUs. In functional magnetic resonance imaging (fMRI), the volume of the data to be processed, and the type of statistical analysis to perform call for high-performance computing strategies. In this work, we present the main features of the R-CUDA package cudaBayesreg which implements in CUDA the core of a Bayesian multilevel model for the analysis of brain fMRI data. The statistical model implements a Gibbs sampler for multilevel/hierarchical linear models with a normal prior. The main contribution for the increased performance comes from the use of separate threads for fitting the linear regression model at each voxel in parallel. The R-CUDA implementation of the Bayesian model proposed here has been able to reduce significantly the run-time processing of Markov chain Monte Carlo (MCMC) simulations used in Bayesian fMRI data analyses. Presently, cudaBayesreg is only configured for Linux systems with Nvidia CUDA support

    From the armed struggle against the dictatorship to the socialist revolution: the narrative restraints to lethal violence among radical left organisations in Portugal

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    This article presents a historical case study of three armed organisations that operated in Portugal before and after the April Revolution of 1974. This event put an end to Estado Novo’s authoritarian regime, starting a period of transition to democracy. The armed organisations operating during Estado Novo sought, essentially, to combat the dictatorship and the Colonial War. These organisations channelled their actions towards the destruction of the regime’s repressive and colonial apparatus, but refused to use lethal violence. During the transition to democracy, disillusionment caused by the negative outcome of the revolutionary process and the end of the utopia of the socialist revolution led some sectors of the radical left to return to armed struggle. This time, such actors targeted both property and human beings but were highly selective in their targeting. We analyse the narratives of restraint of former militants from across these groups, and consider how they were shaped by the evolving socio-political context. In the case of the pre-revolution organisations, we found two collectively accepted narratives inscribed in their genesis: lethal violence as counterproductive and lethal violence as philosophically and ideologically problematic. In the case of the post-revolution organisation we found one restraint narrative shared by the collective: indiscriminate lethal violence is counterproductive. Some militants also developed a restraint narrative that centred on disappointment with the organisation for its perceived operational failures. This study is based on a narrative analysis of data dispersed across personal and public archives, writings, and memoirs of individuals directly and indirectly involved in the armed struggle, with data collected through interviews with former politically violent militants.info:eu-repo/semantics/publishedVersio

    Seismic vulnerability assessment of the old city centre of Seixal, Portugal

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    The seismic vulnerability assessment of old traditional masonry building stocks, in a seismic risk mitigation perspective, is truly essential not only for buildings with recognized historical and patrimonial value, but also, in relation to regular buildings. In this sense, this paper approaches the issue of the seismic vulnerability assessment of masonry buildings through the application of a simplified methodology to building stock of the old city centre of Seixal, Portugal. This methodology is based on a vulnerability index, suitable in the evaluation of damage and in the creation of large scale loss scenarios (economical and human). Over 500 buildings were evaluated in accordance with the referred methodology and the results obtained were then integrated into a Geographical Information System tool. The integration of this kind of vulnerability and loss results into a GIS tool allows that city councils or regional authorities make their decisions based on a global view of the site under analysis, which led to more accurate and faster decisions either in terms of risk mitigation strategies or rehabilitation plans. This tool can also assumes great importance in the construction of safety and rescue plans

    Vulnerability assessment of urban building stock: a hierarchic approach

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    In the last decades the evaluation of the seismic risk are of rising concern, considered essential in the activity and definition of strategy planning and urban management. The evaluation of the seismic vulnerability of the existent building stock in the perspective of the seismic risk mitigation should not be placed only in relation to the isolated buildings of relevant historical and cultural importance, but also, in relation to the agglomerate of buildings in urban centres. The chronological construction process frequently results in characteristic heterogeneity of masonry and wall connection quality. In addition, buildings do not constitute independent units given that they share the mid-walls with adjacent buildings and the façade walls are aligned. This way, as post-seismic observations proved, buildings do not have an independent structural behaviour, but they interact amongst themselves, mainly for horizontal actions and so the structural performance should be studied at the level of the aggregate and not only for each isolated building. In most cases, for masonry structures there is no need for sophisticated dynamic analyses for seismic resistance verification or vulnerability assessment. This is even more relevant when an assessment at the level of a city centre is pursued. In this work, the results of evaluation of the vulnerability will be presented in accordance to three proposed methodologies based on a vulnerability index that consequently allows the evaluation of damage and creation of loss scenarios (economical and human) not only at the level of the building and its façade walls but also at the level of the aggregates. It will be discussed and evaluated the application of the referred methodologies and its integration in an SIG platform

    Arranjos espaciais no consórcio da mandioca com milho e caupi em Presidente Tancredo Neves, Bahia.

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    A consorciação entre culturas permite a exploração na mesma área de mais uma espécie agrícola, sendo vantajoso para a agricultura familiar, considerando que a maioria detém de módulo agrícola com área efetiva de 1 a 3 ha, sendo, portanto, importante para a segurança alimentar, pela exploração de culturas com diferentes exigências edafoclimáticas, reduções na população de plantas infestantes e da perda do solo ocasionada por processos erosivos.Manejo Cultural. Resumo 265

    UNCERTAINTY QUANTIFICATION USING THERMOCOUPLE AND ARDUINO® COMPATIBLE HARDWARE

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    Temperature is a critical aspect in the control of processes in engineering. The measurement, however, must take into account not only the accuracy of the sensor but also the implementation costs and uncertainty. Thermocouples are one of the most widely used temperature measurement methods combining low costs, high measurement ranges, and relatively good accuracy. The acquisition system, however, is usually expensive. This paper evaluated the uncertainty in the temperature measurements of a K-type thermocouple using low cost Arduino® compatible hardware as a data acquisition system. This set was calibrated using a thermostatic distilled water bath at both freezing and boiling phase change points. The equations for uncertainty calculation were fully developed, and the procedures described serve as a reference for uncertainty assessment for thermocouples with other data acquisition systems. Although the calibration was the most significant contributor, the low variability of measurements shows the system has good stability and is a fine choice for industrial applications. The calculations are easy to implement as a routine for several measurements and guarantee results up to the international reference standard

    Tolerância do sorgo forrageiro ao herbicida Primestra SC.

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    Com a finalidade de avaliar a tolerância da cultura do sorgo forrageiro, em três estádios de desenvolvimento, a diferentes doses de Primestra SC (mistura pronta contendo: 200 g l-1 de atrazine + 300 g l-1 de metolachlor), com ou sem adição de Assist (óleo mineral) à calda, foi conduzido um experimento, em condições de casa-de-vegetação, na Embrapa Milho e Sorgo, em Sete Lagoas, MG. Utilizou-se o delineamento de blocos ao acaso, no esquema fatorial (4 x 2 x 3 + 3 ), com quatro repetições. Os tratamentos foram constituídos por quatro doses de Primestra SC (3, 6, 9 e 12 l ha-1), com e sem adição de Assist (1,5 l ha-1), aplicadas em plantas de sorgo forrageiro (AG 2002), em três estádios de desenvolvimento (duas, quatro e seis folhas), acrescentando uma testemunha para cada estádio de desenvolvimento. Foram realizadas avaliações visuais de toxicidade dos herbicidas sobre as plantas de sorgo forrageiro aos 7, 14, 21 e 28 dias após as aplicações (DAA). Aos 28 DAA de cada estádio de desenvolvimento, as plantas foram colhidas, avaliando-se a altura das plantas e a produção de biomassa seca da parte aérea e das raízes. Primestra SC, com adição de Assist, provocou maior toxicidade às plantas de sorgo, comparando-se à aplicação sem adição de Assist, principalmente quando utilizado nas maiores doses. Aplicações mais precoces de Primestra SC (plantas de sorgo com duas folhas) provocaram maior toxicidade à cultura, decrescendo com aplicações mais tardias (plantas com quatro e seis folhas). Verificou-se, todavia, tendência de recuperação do desenvolvimento das plantas em função do tempo, após a aplicação do herbicida, para todas as doses avaliadas, independente do estádio em que foi feita a aplicação
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