496 research outputs found

    Tasking in accelerators: performance evaluation

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    © 2019 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.In this work, we analyze the implications and results of implementing dynamic parallelism, concurrent kernels and CUDA Graphs to solve task-oriented problems. As a benchmark we propose three different methods for solving DGEMM operation on tiled-matrices; which might be the most popular benchmark for performance analysis. For the algorithms that we study, we present significant differences in terms of data dependencies, synchronization and granularity. The main contribution of this work is determining which of the previous approaches work better for having multiple task running concurrently in a single GPU, as well as stating the main limitations and benefits of every technique. Using dynamic parallelism and CUDA Streams we were able to achieve up to 30% speedups and for CUDA Graph API up to 25x acceleration outperforming state of the art results.This project has received funding from the EPEEC project from the European Union’s Horizon 2020 research and innovation programme under grant agreement No 801051, from the Spanish Ministry of Economy and Competitiveness under the project Computación de Altas Prestaciones VII ( TIN2015-65316-P ) and the Departament d’Innovació, Universitats i Empresa de la Generalitat de Catalunya, under project MPEXPAR: Models de Pro-gramació i Entorns d’Execució Paral·lels (2014-SGR-1051 ). Finally, this project also received funding from the Spanish Ministry of Economy and Competitiveness under the Juan de la Cierva Grant Agreement No IJCI-2017-33511 , and from the European Union’s Horizon 2020 research and innovation program under the Marie Sklodowska Curie grant agreement No. 749516 .Peer ReviewedPostprint (author's final draft

    Alterations on the evapotranspiration of sugarcane cultivars under distinct salinity levels applied in the fertigation

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    The aim of this research was to evaluate the effect of distinct levels of salinity on the evapotranspiration of the RB867515, RB855453, RB92579 and RB928064 sugarcane cultivars. The evapotranspiration was monitored during daytime period under meteorological conditions influenced, mainly by cloud variations. The salinity values were established by addition of 0, 50, 100 and 150 mM of Sodium Chloride (NaCl) to the nutrient solution, which was applied by fertigation, in such way that the electrical conductivity (EC) of the leached solution was near 3, 6, 10 and 13 dS m -1 , respectively. The increase of the NaCl concentration in the nutrient solution affected, significantly and in a linear manner, the evapotranspiration of all sugarcane cultivars, such that the days with low cloud provided the highest evapotranspiration values and the greater reduction among salinity levels. Analysis of the evapotranspiration accumulated during the daytime period showed that there were no significant differences among sugarcane cultivars and that, under the highest atmospheric water demand, the evapotranspiration decreased 48.5 g plant -1 EC -1 . This value represents the average reduction of 5.1% EC -1 when compared to the treatment without NaCl, considering data of all cultivars

    U B V R I Photometry of Stellar Structures throughout the Disk of the Barred Galaxy NGC 3367

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    We report new detailed surface U, B, V, R, and I photometry of 81 stellar structures in the disk of the barred galaxy NGC 3367. The images show many different structures indicating that star formation is going on in the most part of the disk. NGC 3367 is known to have a very high concentration of molecular gas distribution in the central regions of the galaxy and bipolar synchrotron emission from the nucleus with two lobes (at 6 kpc) forming a triple structure similar to a radio galaxy. We have determined the U, B, V, R, and I magnitudes and U - B, B - V, U - V, and V - I colors for the central region (nucleus), a region which includes supernovae 2003 AA, and 79 star associations throughout NGC 3367. Estimation of ages of star associations is very difficult due to several factors, among them: filling factor, metallicity, spatial distribution of each structure and the fact that we estimated the magnitudes with a circular aperture of 16 pixels in diameter, equivalent to 6.81.46''.8\sim1.4 kpc. However, if the colors derived for NGC 3367 were similar to the colors expected of star clusters with theoretical evolutionary star tracks developed for the LMC and had a similar metallicity, NGC 3367 show 51 percent of the observed structures with age type SWB I (few tens of Myrs), with seven sources outside the bright surface brightness visible disk of NGC 3367.Comment: Accepted for publication (abr 2007) in The Astronomical Journal (July 2007 issue

    Uranyl complexes formed with apara-t-butylcalix[4]arene bearing phosphinoyl pendant arms on the lower rim. Solid and solution studies

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    The current interest in functionalized calixarenes with phosphorylated pendant arms resides in their coordination ability towards f elements and capability towards actinide/rare earth separation. Uranyl cation forms 1:1 and 1:2 (M:L) complexes with atetra-phosphinoylated p-tert-butylcalix[4]arene, B4bL4: UO2(NO3)2(B4bL4)n· xH2O (n = 1, x = 2, 1; n = 2, x = 6, 2). Spectroscopic data point to the inner coordination sphere of 1 containing one monodentate nitrate anion, one water molecule and the four phosphinoylated arms bound to UO22+ while in 2, uranyl is only coordinated to calixarene ligands. In both cases the U(VI) ion is 8-coordinate. Uranyl complexes display enhanced metal-centred luminescence due to energy transfer from the calixarene ligands; the luminescence decays are bi-exponential with associated lifetimes in the ranges 220μs <τs <250μs and 630μs <τL < 640μs, pointing to the presence of two species with differently coordinated calixarene, as substantiated by aXPS study of U(4f5/2,7/2), O(1s) and P(2p) levels on solid state samples. The extraction study of UO22+ cation and trivalent rare-earth (Y, La, Eu) ions from acidic nitrate media by B4bL4 in chloroform shows the uranyl cation being much more extracted than rare earth

    Kinetics of echinostoma caproni (trematoda: echinostomatidae) antigens in feces and serum of experimentally infected hamsters and rats

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    This study reports on the kinetics of antibody production to Echinostoma caproni and the dynamics of antigens in feces and sera in 2 experimental hosts (hamsters and rats) that display different degrees of susceptibility with this echinostome. Echinostoma caproni produced chronic infections in hamsters, whereas rats lost the infection at 49–56 days postinfection (DPI). Hamsters developed higher antibody responses than rats, probably in relation to different intestinal absorptions of worm antigens in each host species. The levels of coproantigens were indicative of the course of infection in each host. Positive coproantigen levels were detected at 1–2 DPI in both hosts, and the values remained positive until the end of the experiment in hamsters; in rats, the coproantigen levels reverted to negative values, coinciding with the loss of infection. High levels of circulating antigens were detected in hamsters from 21 DPI to the end of the study. In contrast, low levels of E. caproni seroantigens were detected in rats only. These observations may reflect the differences in local inflammatory responses induced by E. caproni in each host species.Toledo Navarro, Rafael, [email protected] ; Espert Fernandez, Ana M., [email protected] ; Marcilla Diaz, Antonio, [email protected] ; Esteban Sanchis, Jose Guillermo, [email protected]

    Seismic Analysis of Axisymmetric Shells

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    Dynamic analysis of shells structures subjected to seismic loadings is one of the basic requirements in the safety assessment of nuclear power plants. Typical examples of such structures are steel containment vessels that house the primary cooling system, cooling towers and the concrete reactor building that serves as a missile and biological shield for the containment vessel. In this work we study axisymmetric shells subjected to multiple support excitation.The shells are spatially discretized by the finite element method and in order to obtain estimatives for the maximum values of displacements and stresses, the response spctrum technique is used. Finally some numerical results are presented and discussed in the case of a shell of revolution with vertical symmetry axis, subjected to seismic ground motions in the horizontal, vertical and rocking directions

    Proyecto Veranes: arqueología e historia en torno a la vía de la Plata en el Concejo de Gijón (Asturias)

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    Se presentan en estas páginas los objetivos, los planteamientos metodológicos y los primeros resultados del "Proyecto Veranes", yacimiento tardorromano y medieval situado en las proximidades de la ciudad de Gijón. Dicho proyecto, financiado mayoritariamente por el Ilmo. Ayuntamiento de Gijón, es el fruto de un esfuerzo coordinado entre diversas instituciones públicas

    Shallow foundations for offshore wind towers

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    Direct foundations are present in about 25% of the installed offshore wind power towers. The peculiarities of this type of structure are well known: high dynamic sensitivity, complex couplings between environmental actions, machine operation and structural response, complex installation and maintenance, difficult site investigation. There is a clear need for optimized foundation design tools that would enable cost reduction and a more detailed assessment of the risk of every installation. One such tool is likely to be the systematic use of failure envelopes for capacity checks. The paper explores the benefits of such an approach with various realistic design examples.Postprint (published version

    Development of an antibody-based capture enzyme-linked immunosorbent assay for detecting echinostoma caproni (trematoda) in experimentally infected rats: kinetics of coproantigen excretion

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    The present study reports on the development of a coproantigen capture enzyme-linked immunosorbent assay (ELISA) for detecting Echinostoma caproni in experimentally infected rats. The capture ELISA was based on polyclonal rabbit antibodies that recognize excretory–secretory (ES) antigens. The detection limit of pure ES was 3 ng/ml in sample buffer and 60 ng/ml in fecal samples. The test was evaluated using a follow-up of 10 rats experimentally infected with 100 metacercariae of E. caproni, and the results were compared with those of other diagnostic methods such as parasitological examination and antibody titers determined by indirect ELISA. Coproantigens were detected in all the infected rats from the first day postinfection (DPI). The period of maximal coproantigen excretion was between 7 and 21 DPI. The values remained positive until 49–56 DPI, coinciding with the disappearance of the eggs in the stool samples of the infected rats. The kinetics of coproantigen detection were correlated with those of egg output. The present assay provides an alternative tool for the diagnosis of the echinostome infections. The proposed capture ELISA makes possible an earlier diagnosis than that provided by parasitological examination and indirect ELISA and also allows for the differentiation of past and current infections. Our results show that this assay can also be used to monitor the course of echinostome infections.Toledo Navarro, Rafael, [email protected] ; Espert Fernandez, Ana M., [email protected] ; Marcilla Diaz, Antonio, [email protected] ; Esteban Sanchis, Jose Guillermo, [email protected]

    Balanço de Energia para uma Cultura de Cana-de-açúcar no Estado de Alagoas

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    Balanço de energia para uma cultura de cana-de-açúcar noestado de Alagoa
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