Surface tension implementation for Gensmac 2D

In the present work we describe a method which allows the incorporation of surface tension into the GENSMAC2D code. This is achieved on two scales. First on the scale of a cell, the surface tension effects are incorporated into the free surface boundary conditions through the computation of the capillary pressure. The required curvature is estimated by fitting a least square circle to the free surface using the tracking particles in the cell and in its close neighbors. On a sub-cell scale, short wavelength perturbations are filtered out using a local 4-point stencil which is mass conservative. An efficient implementation is obtained through a dual representation of the cell data, using both a matrix representation, for ease at identifying neighbouring cells, and also a tree data structure, which permits the representation of specific groups of cells with additional information pertaining to that group. The resulting code is shown to be robust, and to produce accurate results when compared with exact solutions of selected fluid dynamic problems involving surface tension

Mechanical behavior of low carbon steel subjected to strain path changes: Experiments and modeling

The mechanical response of a low carbon steel under complex strain path changes is analyzed here in terms of dislocation storage and annihilation. The mechanical tests performed are cyclic shear and tensile loading followed by shear at different angles with respect to the tensile axis. The material behavior is captured by a dislocation-based hardening model, which is embedded in the Visco-Plastic Self-Consistent (VPSC) polycrystal framework taking into account the accumulation and annihilation of dislocations, as well as back-stress effects. A new and more sophisticated formulation of dislocation reversibility is proposed. The simulated flow stress responses are in good agreement with the experimental data. The effects of the dislocation-related mechanisms on the hardening response during strain path changes are discussed. (C) 2016 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.11158Ysciescopu

Numerical simulation of drop impact and jet buckling problems using the eXtended Pom-Pom model

This work presents numerical simulations of two fluid flow problems involving moving free surfaces: the impacting drop and fluid jet buckling. The viscoelastic model used in these simulations is the eXtended Pom-Pom (XPP) model. To validate the code, numerical predictions of the drop impact problem for Newtonian and Oldroyd-B fluids are presented and compared with other methods. In particular, a benchmark on numerical simulations for a XPP drop impacting on a rigid plate is performed for a wide range of the relevant parameters. Finally, to provide an additional application of free surface flows of XPP fluids, the viscous jet buckling problem is simulated and discussed. (C) 2011 Elsevier B.V. All rights reserved.CNPq (Conselho Nacional de Desenvolvimento Cientifico e Tecnologico) [477858/2009-0, 305447/2010-6, 302631/2010-0, 471793/2010-8]Conselho Nacional de Desenvolvimento Cientifico e Tecnologico (CNPq)Fundacao de Amparo a Pesquisa do Estado de Sao Paulo (FAPESP)FAPESP (Fundacao de Amparo a pesquisa do Estado de Sao Paulo) [2009/15892-9]CAPESCAPES [BEX 2844/10-9]FCTFCTFEDER [PTDC/EME-MFE/114322/2009]FEDE

Mechanical behavior of Mg subjected to strain path changes: Experiments and modeling

Two-step tension tests with reloads along different directions are performed on rolled Mg alloy sheet at room temperature. The experimental yield stress at reloading is systematically lower than before unloading. Such a behavior is captured by a microstructure-based hardening model accounting for dislocation reversibility and back-stress. This formulation, embedded in the Visco-Plastic Self-Consistent (VPSC) model, links the dislocation density evolution throughout the deformation with hardening. The predicted results agree well with the experimental data in terms of flow stress response and texture evolution. The effects of texture anisotropy and back-stress on the mechanical response during the strain path change are discussed. (C) 2014 Elsevier Ltd. All rights reserved.112619Ysciescopu

Application of a renormalization group algorithm to nonequilibrium cellular automata with one absorbing state

We improve a recently proposed dynamically driven renormalization group algorithm for cellular automata systems with one absorbing state, introducing spatial correlations in the expression for the transition probabilities. We implement the renormalization group scheme considering three different approximations which take into account correlations in the stationary probability distribution. The improved scheme is applied to a probabilistic cellular automaton already introduced in the literature.Comment: 7 pages, 4 figures, to be published in Phys. Rev.

Burden and severity of children's hospitalizations by respiratory syncytial virus in Portugal, 2015-2018

Background Respiratory syncytial virus (RSV) is a leading cause of acute lower respiratory infection (ALRI) in young children and is of considerable burden on healthcare systems. Our study aimed to evaluate ALRI hospitalizations related to RSV in children in Portugal. Methods We reviewed hospitalizations potentially related to RSV in children aged <5 years from 2015 to 2018, using anonymized administrative data covering all public hospital discharges in mainland Portugal. Three case definitions were considered: (a) RSV-specific, (b) (a) plus unspecified acute bronchiolitis (RSV-specific & Bronchiolitis), and (c) (b) plus unspecified ALRI (RSV-specific & ALRI). Results A total of 9697 RSV-specific hospitalizations were identified from 2015 to 2018—increasing to 26 062 for RSV-specific & ALRI hospitalizations—of which 74.7% were during seasons 2015/2016–2017/2018 (November–March). Mean hospitalization rates per season were, for RSV-specific, RSV-specific & Bronchiolitis, and RSV-specific & ALRI, respectively, 5.6, 9.4, and 11.8 per 1000 children aged <5 years and 13.4, 22.5, and 25.9 in children aged <2 years. Most RSV-specific hospitalizations occurred in healthy children (94.9%) and in children aged <2 years (96.3%). Annual direct costs of €2.4 million were estimated for RSV-specific hospitalizations—rising to €5.1 million for RSV-specific & ALRI—mostly driven by healthy children (87.6%). Conclusion RSV is accountable for a substantial number of hospitalizations in children, especially during their first year of life. Hospitalizations are mainly driven by healthy children. The variability of the potential RSV burden across case definitions highlights the need for a universal RSV surveillance system to guide prevention strategies

Rendimento e composição química de cultivares de milho em moagem a seco e produção de grits.

O milho é uma das principais matérias-primas para a indústria de alimentos. Desse cereal, é possível obter óleo, fubá, canjica, grits, farelo, amido e zeína. Conduziu-se este trabalho com o objetivo de avaliar o rendimento de moagem a seco, produção de grits e composição química de 16 cultivares de milho. Os grãos de milho das 16 cultivares avaliadas tiveram a sua umidade padronizada para 12% e foram submetidos a um processo de limpeza em uma mesa gravimétrica. Encerrada a etapa de limpeza, foram colocados 10 kg de grãos de cada cultivar em degerminador de facas com rotação de 600 rpm por um período de 10 minutos. Após a degerminação, o endosperma foi passado por moinho de rolos corrugados com distância entre rolos de 30 ?m. O material moído foi submetido à tamisação em peneiras de 14, 20, 25 e 30 mesh por um período de 10 minutos. Para a degerminação, o delineamento experimental utilizado foi o inteiramente casualizado, com um fator de 16 cultivares e 2 repetições. Na tamisação, o delineamento usado foi com dois fatores: 16 cultivares, 5 peneiras e 2 repetições. A cultivar BR-106, o híbrido duplo BRS-2114 e o híbrido triplo BR-3123 registraram maiores rendimentos (P<0,05) na fração endosperma. Na tamisação, a fração avaliada foi a retida em peneira de 20 mesh, por causa da utilização de grits com essas dimensões como matéria-prima na indústria de snacks. Os híbridos triplos BR-3123, BRS-3101 e BR 106 foram os mais produtivos na peneira de 20 mesh, sendo os mais indicados para a indústria produtora de grits, fornecedora de matéria-prima para a indústria de alimentos, entre essas, as de snacks e a de bebida

Detection of the Cherenkov light diffused by Sea Water with the ULTRA Experiment

The study of Ultra High Energy Cosmic Rays represents one of the most challenging topic in the Cosmic Rays and in the Astroparticle Physics fields. The interaction of primary particles with atmospheric nuclei produces a huge Extensive Air Shower together with isotropic emission of UV fluorescence light and highly directional Cherenkov photons, that are reflected/diffused isotropically by the impact on the Earth's surface or on high optical depth clouds. For space-based observations, detecting the reflected Cherenkov signal in a delayed coincidence with the fluorescence light improves the accuracy of the shower reconstruction in space and in particular the measurement of the shower maximum, giving a strong signature for discriminating hadrons and neutrinos, and helping to estimate the primary chemical composition. Since the Earth's surface is mostly covered by water, the ULTRA (UV Light Transmission and Reflection in the Atmosphere)experiment has been designed to provide the diffusing properties of sea water, overcoming the lack of information in this specific field. A small EAS array, made up of 5 particle detectors, and an UV optical device, have been coupled to detect in coincidence both electromagnetic and UV components. The detector was in operation from May to December, 2005, in a small private harbor in Capo Granitola (Italy); the results of these measurements in terms of diffusion coefficient and threshold energy are presented here.Comment: 4 pages, 3 figures, PDF format, Proceedings of 30th ICRC, International Cosmic Ray Conference 2007, Merida, Yucatan, Mexico, 3-11 July 200