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Design and Implementation of an Extended Collectives library for Unified Parallel C

Journal of Computer Science & Technology 2013年第1期28卷 72-89页

作者： Carlos Teijeiro guillermo l.taboada Juan Tourio Ramón Doallo Jos C.Mourio Damivn A.Mallón Brian Wibecan Computer Architecture Group University of A Corua Galicia Supercomputing Center Jlich Supercomputing Centre Institute for Advanced SimulationForschungszentrum Jlich Industry Standard Servers Group Hewlett-Packard Company

Unified Parallel C （UPC） is a parallel extension of ANSI C based on the Partitioned Global Address Space （PGAS） programming model, which provides a shared memory view that simplifies code development while it can take advantage of the scalability of distributed memory architectures. Therefore, UPC allows programmers to write parallel applications on hybrid shared/distributed memory architectures, such as multi-core clusters, in a more productive way, accessing remote memory by means of different high-level language constructs, such as assignments to shared variables or collective primitives. However, the standard UPC collectives library includes a reduced set of eight basic primitives with quite limited functionality. This work presents the design and implementation of extended UPC collective functions that overcome the limitations of the standard collectives library, allowing, for example, the use of a specific source and destination thread or defining the amount of data transferred by each particular thread. This library fulfills the demands made by the UPC developers community and implements portable algorithms, independent of the specific UPC compiler/runtime being used. The use of a representative set of these extended collectives has been evaluated using two applications and four kernels as case studies. The results obtained confirm the suitability of the new library to provide easier programming without trading off performance, thus achieving high productivity in parallel programming to harness the performance of hybrid shared/distributed memory architectures in high performance computing.

关键词： Unified Parallel C collective operation programmability partitioned global address space high performance computing

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Global pattern of conodont similarity and faunal constraints during the highstand of the Evae eustatic event(late Floian,lower Ordovician)

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Journal of Palaeogeography 2024年第4期13卷 883-905页

作者： Gisella M.Della Costa guillermo l.Albanesi CiGEA Facultad de Ciencias ExactasFisicas y NaturalesUniversidad Nacional de CordobaAv.Vélez GEAFacuitadaeCienciasExactasFisicas Sarsfield 299X5000GCB CordobaArgentina

One of the largest Ordovician sea-level rises is the Evae transgression,which occurs in the lower part of the Oepikodus evae Biozone,indicative of a late Floian ***,the characteristics associated with the highstand of this event included:a higher proportion of specimens of the index species *** than other species,a diversity acme in the evae Biozone,and a reduction of biogeographic barriers that resulted in a high proportion of species with cosmopolitan *** the present contribution,the pattern of species similarity among laurentia,Argentine Precordillera,Baltica,Kazakhstania,South China,and Australia is evaluated with a multiple coefficient analysis including only the sections that recorded the highstand of the Evae ***,the effect of possible terrestrial,latitudinal,physicochemical barriers and palaeogeographic distance on the species distribution is statistically *** results show a global pattern of conodont species distribution that is highly constrained by the tested palaeoenvironmental *** suggests that contrary to what was expected for a prominent transgression,faunal barriers did not decrease significantly during the Evae drowning peak.

关键词： Evae transgression Oepikodus evae Biozone Statistical analyses Faunal similarities Palaeoenvironmental barriers

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Macrobioerosion and Microbioerosion in Marine Molluscan Shells from Holocene and Modern Beaches (39°-40°S, South of Buenos Aires Province, Argentina)

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Acta Geologica Sinica(English Edition) 2017年第4期91卷 1215-1230页

作者： Melisa P. CHARO Jose l. CAVAllOTTO guillermo ACENOlAZA Instituto Superior de Correlacion Geologica (INSUGEO/CONICET-UNT) Miguel lillo 205 4000 Tucuman Argentina Servicio de Hidrografia Naval Av. Montes de Oca 2124 C1270ABWBuenos Aires Argentina

The marine sediments of the area of Verde Peninsula - Jabali Island （39°28＇S/62°19%V-40°28＇ S/62°11＇W） Holocene in age （3-2 ky）, and modern beaches contain a significant amount of bioeroded mollusc shells. Fifteen sites were analyzed, in which 20.11% of the mollusc shells （2168 valves） presented bioerosion traces, in 54 species （30 bivalves and 24 gastropods）. Fourteen ichnogenera were reported： Entobia, Maeandropolydora, Iramena, Caulostrepsis, Pennatichnus, Pinaceocladichnus, Trypanites, and Gastrochaenolites （Domichnia）, Gnathichnus and Radulichnus （Pascichnia）, Finichnus and Centrichnus （Fixichnia）, Oichnus （Praedicnia）（macrobioerosion）, y Semidendrina （microbioerosion）, the latter is first reported in mollusc shells in Argentina. Eleven ichnospecies were identified Finichnus peristroma, Maeandropolydora sulcans, Gnathichnus pentax, Pinaceocladichnus onubensis, Caulostrepsis taeniola, Centrichnus eccentricus, Radulichnus inopinatus, Oichnus simplex, Oichnus paraboloides, Oichnus gradatus, and Gastrochaenolites torpedo （lithic remains）. The dominant ichnogenera in the Holocene deposits are Iramena, Entobia and Oichnus. The same ichnogenera are constant with different abundance in the modern beaches, and increasing representation of Pinaceocladichnus and Pennatichnus. The dominant ichnofacies in the Holocene deposits is Trypanites, revealing a benthonic marine community composed of cheilostome bryzoans, clionaid sponges, predator gastropods, regular echinoids, polychaete annelids, bivalves, thallophytas and fungi. Generally, the area was described as a sublittoral, low-energy, stable environment with high rate of oxygenation, and sandy bottoms, with rocky bottoms at Villalonga locality.

关键词： molluscan bioerosion Holocene south of Buenos Aires Province

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Graphic correlation of Argentine Precordillera and North American lower/Middle Ordovician sections

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Episodes 2006年第1期29卷 16-19页

作者： Walter C. Sweet guillermo l. Albanesi Department of Geological Sciences The Ohio State University Columbus Ohio 43210 USA CONICET - Museo de Paleontologia Universidad Nacional de Cordoba C. C. 1598 5000 Cordoba Argentina.

Present work demonstrates that a level equivalent to the proposed Whiterockian basal GSSP can be located graphically in a composite section anchored by the Niquivil section of the Argentine Precordillera. The FAD ofCooperignathus aranda in the Niquivil composite section, a candidate for GSSP of the lower/Middle Ordovician boundary, projects to a level very close to the FAD of Tripodus laevis in the Whiterockian reference section. The conodont-based framework reported here includes the potential for recognition of the proposed Whiterock Canyon-based GSSP, the Cooperignathus aranda-based GSSP, and, possibly, the Baltoniodus triangularisbased GSSP, recently proposed.

关键词：奥陶纪美国相关性阿根廷生物地层学

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Nesting innovations allow population growth in an invasive population of rose-ringed parakeets

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Current Zoology 2022年第6期68卷 617-626页

作者： Dailos HERNANDEZ-BRITO Jose l.TEllA guillermo BlANCO Martina CARRETE Department of Conservation Biology Donana Biological Station(CSIC)Calle Americo Vespucio26Sevilla 41092Spain Department of Evolutionary Ecology Museo Nacional de Ciencias Naturales(CSIC)Calle JoseGutierrez Abascal2Madrid 28006Spain Department of Physical Chemical and Natural SystemsUniversidad Pablo de OlavideCarretera de Utrerakm 1Sevilla 41013Spain

Certain traits of recipient environments,such as the availability of limiting resources,strongly determine the establishment success and spread of non-native *** limitations may be overcome through behavioral plasticity,allowing them to exploit alternative ***,we show how a secondary cavity nester bird,the rose-ringed parakeet Psittacula krameri,innovates its nesting behavior as a response to the shortage of tree cavities for nesting in its invasive range in Tenerife(Canary Islands).We observed that some breeding pairs excavated their own nest cavities in palms,thus becoming primary cavity nester,whereas others occupied nests built with wood sticks by another invasive species,the monk parakeet Myiopsitta *** use of these novel nesting strategies increased the number of breeding pairs by up to 52%over 6 years,contributing to a 128.8%increase of the whole *** nests were located at greater heights above ground and were more aggregated around conspecifics but did not result in greater breeding success than natural *** of monk parakeet colonies by rose-ringed parakeets also benefited the former species through a protective-nesting association against nest *** results show how an invasive species innovate nesting behaviors and increase nest-site availability in the recipient environment,thus facilitating its population growth and invasion *** behavioral innovations in other invasive rose-ringed parakeet populations may be overlooked,and should be considered for effective management plans.

关键词： antipredator response behavioral flexibility biological invasions cavity nesters nesting innovation reproductive success

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Properties of nuclear pastas

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Frontiers of physics 2021年第2期16卷 119-173页

作者： Jorge A.lopez Claudio O.Dorso guillermo Frank Department of Physics University of Texax at El PasoEl PasoTexas 79968USA Departamento de Fisica FCENUniversidad de Buenos AiresNunezArgentina Unidad de Investigacion y Desarrollo de las Ingenierias Universidad Tecnologica NacionalFacultad Regional Buenos AiresBuenos AiresArentina

In this review we study the nuclear pastas as they are expected to be formed in neutron star *** start with a study of the pastas formed in nuclear matter(composed of protons and neutrons),we follow with the role of the electron gas on the formation of pastas,and we then investigate the pastas in neutron star matter(nuclear matter embedded in an electron gas).Nuclear matter(NM)at intermediate temperatures(1 MeV≤T≤***),at saturation and and sub-saturation densities,and with proton content ranging from 30%to 50%was found to have liquid,gaseous and liquid-gas mixed *** isospin-dependent phase diagram was obtained along with the critical points,and the symmetry energy was calculated and compared to experimental data and other *** low temperatures(T≤1 MeV)NM produces crystal-like structures around satura-tion densities,and pasta-like structures at sub-saturation *** of the pasta structures were studied with cluster-recognition algorithms,caloric curve,the radial distribution function,the lindemann coefficient,Kolmogorov statistics,Minkowski functionals;the symmetry energy of the pasta showed a connection with its *** star matter(NSM)is nuclear matter embedded in an electron *** electron gas is included in the calculation by the inclusion of an screened Coulomb *** connect the NM pastas with those in neutron star matter(NSM),the role the strength and screening length of the Coulomb interaction have on the formation of the pastas in NM was *** was found to exist even without the presence of the electron gas,but the effect of the Coulomb interaction is to form more defined pasta structures,among other ***,it was determined that there is a minimal screening length for the developed structures to be independent of the cell *** star matter was found to have similar phases as NM,phase transitions,symmetry energy,structure function and thermal *** in NM,pasta f

关键词： nuclear pasta neutron star matter nuclear symmetry energy molecular dynamics nuclear phase transitions

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A proposed Global Boundary Stratotype Section and Point for the base of the Middle Ordovician Series： The Niquivil section, Precordillera of San Juan, Argentina

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Episodes 2006年第1期29卷 1-15页

作者： guillermo l. Albanesi Marcelo G. Carrera Fernando l. Canas Matthew Saltzman CONICET - Facultad de Ciencias Exactas Fisicas y Naturales Universidad Nacional de Córdoba Casilla de Correo 1598 5000 Córdoba Argentina CONICET- Departamento de Geologfa Universidad Nacional de Rio Cuarto Ruta Nacional 36 km 601 5800 Rio Cuarto Argentina Department of Geological Sciences The Ohio State University Columbus OH 43210 USA.

The Niquivil section, Argentine Precordillera, fulfills most of the requirements for a Global Stratotype Section and Point （GSSP） for the base of the Middle Ordovician Series. It has excellent conodont biostratigraphy in a continuous succession of uniform lithology, is readily accessible, and the critical interval is not tectonically affected. The position of the lower/Middle Ordovician Series boundary in the Central Precordillera is placed at the middle part of the San Juan Formation, an open-platform carbonate unit. The Niquivil section is proposed as a GSSP for the base of the Middle Ordovician, which is marked by the FAD of the conodont Cooperignathus aranda （Cooper）. It occurs in level NCA, at the upper part of the Oepikodus evae Zone （overlapping uppermost records of O. evae in association with other guide species）; i.e., 100.15 m above the base of the reference section. The auxiliary Pena Sombria section from northern Precordillera records graptolites of the lower （but not lowest） Middle Ordovician in the Isograptus victoriae maximus Zone, few meters above the proposed boundary biohorizon. The range of C. aranda can be correlated with the I. victoriae lunatus Zone up to the lower part of the Undulograptus austrodentatus Zone in diverse sections of the world. C. aranda presents cosmopolitan distribution and occurs in virtually all environments. The proposed GSSP preserves a carbon-isotope record that provides an auxiliary marker of potential global application. Radiometric dating of K-bentonite samples, interbedded with carbonate strata yielding lower records of C. aranda, were recovered from the auxiliary Talacasto section in Central Precordillera （469.8 ±2.3 Ma, U-Pb SHRIMP dating）.

关键词：奥陶纪阿根廷界线层型 GSSP 生物地层学

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Using Cartesian Slice Plots of a Cosmological Simulation as Input of a Convolutional Neural Network

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Research in Astronomy and Astrophysics 2024年第11期24卷 225-242页

作者： guillermo Arreaga-García Departamento de Investigación en Física Universidad de Sonora.Apdo.Postal 14740C.P.83000HermosilloSonoraMexico

Using a uniform partitioning of cubic cells,we cover the total volume of aΛCDM cosmological simulation based on *** define a visualization cell as a spatial extension of the cubic cell,so that we collect all simulation particles contained in this visualization cell to create a series of Cartesian plots in which the overdensity of matter is clearly *** then use these plots as input to a convolutional neural network(CNN)based on the Keras library and TensorFlow for image *** assign a class to each plot,we approximate the Hessian of the gravitational potential in the center of the cubic *** selected cubic cell is then assigned a label of 1,2 or 3,depending on the number of positive eigenvalues obtained for the Householder reduction of the Hessian *** apply the CNN to several models,including two models with different visualization volumes,one with a cell size of type l(large)and the other with a cell type S(small).A third model combines the plots of the previous l and S cell *** far,we have mainly considered a slice parallel to the XY plane to make the *** last model is considered based on visualizations of cells that also include slices parallel to the ZX and ZY *** find that the accuracy in classification plots is acceptable,and the ability of the models to predict the class works *** results allow us to demonstrate the aim of this paper,namely that the usual Cartesian plots contain enough information to identify the observed structures of the cosmic web.

关键词： methods numerical cosmology theory (cosmology:)large scale structure of universe

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Nestling sex ratio is unaffected by individual and population traits in the griffon vulture

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Current Zoology 2023年第3期69卷 227-235页

作者： guillermo Gomez-lopez Felix Martinez Ana Sanz-Aguilar Martina Carrete guillermo Blanco Department of Evolutionary Ecology National Museum of Natural Sciences(MNCN)Spanish National Research Council(CSiC)Jose Gutierrez Abascal 228006 MadridSpain Escuela Internacional de Doctorado Universidad Rey Juan Carlos(URJC)Tulipan s/n28933 MostolesMadridSpain Animal Demography and Ecology Group Institut Mediterrani d'Estudis Avangats(IMEDEA)Miquel Marques 217020 EsporlesMallorcaSpain Applied Zoology and Conservation Group Universitat de les Illes Balears(UIB)Ctra.De Valldemossa km.7.507122PalmaSpain Department of Physical Chemical and Natural SystemsUniversidad Pablo de Olavide(UPO)Ctra.de Utrera km.141013 SevillaSpain

Variation in offspring sex ratios is a central topic in animal demography and population *** studies have focused on bird species with marked sexual dimorphism and multiple-nestling broods,where the offspring sex ratio is often biased due to different individual or environmental ***,biases in offspring sex ratios have been far less investigated in monomorphic and single-egg laying species,and few studies have evaluated long-term and large-scale variations in the sex ratio of nestling ***,we explore individual and environmental factors potentially affecting the secondary sex ratio of the monomorphic griffon vulture Gyps *** used information collected at three breeding nuclei from central Spain over a 30-year period(1990–2020)to analyse the effects of nestling age,parental age,breeding phenology,conspecific density,population reproductive parameters,and spatial and temporal variability on nestling *** ratio did not differ from parity either at the population or the nuclei *** significant between-year differences were detected,even under highly changing conditions of food availability associated with the mad-cow *** found that tree nesting breeders tend to have more sons than daughters,but as this nesting behavior is rare and we consequently have a small sample size,this issue would require additional *** further research is needed to assess the potential effect of breeder identity on nestling sex ratio,this study contributes to understanding the basic ecology and population dynamics of Griffon Vultures,a long-lived species with deferred maturity and low fecundity,whose minor deviations in the offspring sex ratio might imply major changes at the population level.

关键词： offspring sex ratio nestling sex Gyps fulvus monomorphism mad-cow crisis demography

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Design and optimization of supersonic turbines for detonation combustors

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Chinese Journal of Aeronautics 2022年第11期35卷 33-44页

作者： Jorge SOUSA Elena COllADO-MORATA guillermo PANIAGUA Flemish InstituteforTechnological Research Mol 2400Belgium Commissariat à lénergie atomique et aux énergies alternatives Le Barp 33114France Mechanical Engineering Purdue UniversityWest-Lafayette IN 47906USA

Detonation-based engines offer a potential surge in efficiency for compact thermal power systems. However, these cycles require ad-hoc components adapted to the high outlet velocity from the detonation combustors. This paper presents the design methodology of turbine stages suitable for supersonic inlet conditions and provides a detailed analysis of optimized turbine geometries. A reduced-order solver examines the supersonic blade rows’ functional design space, quantifies the turbine’s non-isentropic performance, and budgets the turbine loss for different optimized leading-edge designs and chord to pitch ratios. The shock-wave interactions were identified as the predominant contributor to turbine losses, and optimal pitch-chord ratios were determined for various inlet Mach numbers. Finally, with this tool, the specific-power output for a wide range of design configurations was computed;and the metal angle that ensures flow starting and maximizes power extraction was calculated. The detailed numerical study describes the flow interactions in a supersonic turbine and offers new correlations to guide the design of future supersonic turbines.

关键词： Rotating detonation Shock waves Supersonic flow Turbines Unstarting

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