62 research outputs found

    "Breathing" rogue wave observed in numerical experiment

    Full text link
    Numerical simulations of the recently derived fully nonlinear equations of motion for weakly three-dimensional water waves [V.P. Ruban, Phys. Rev. E {\bf 71}, 055303(R) (2005)] with quasi-random initial conditions are reported, which show the spontaneous formation of a single extreme wave on the deep water. This rogue wave behaves in an oscillating manner and exists for a relatively long time (many wave periods) without significant change of its maximal amplitude.Comment: 6 pages, 12 figure

    Variabilidade espacial dos atributos físicos e químicos de solo e planta na UP Uva para Vinho, Bento Gonçalves, RS.

    Get PDF
    Tecnologias de agricultura de precisão (AP) são pouco contempladas pelo setor primário para aumentar a qualidade e competitividade do vinho brasileiro. Por isso, esta pesquisa considera várias tecnologias de AP num vinhedo do cv. Merlot, clone 347, UP Uva para Vinho, localizado em Bento Gonçalves, RS. Neste resumo apresentam-se resultados preliminares relacionados à análise da variabilidade espacial dos atributos físicos e químicos de solo e planta, complementando o trabalho de Miele et al. (2011), também apresentado neste workshop. Os dados sugerem haver variabilidade espacial significativa para vários atributos, com boa correlação com as classes taxonômicas de solo (Argissolos, Cambissolos e Neossolos) e, em certos casos, dependência com o manejo realizado no vinhedo. Os próximos passos consistem em afinar a espacialização dos dados e definir métodos adequados de integração

    Comparison between three-dimensional linear and nonlinear tsunami generation models

    Get PDF
    The modeling of tsunami generation is an essential phase in understanding tsunamis. For tsunamis generated by underwater earthquakes, it involves the modeling of the sea bottom motion as well as the resulting motion of the water above it. A comparison between various models for three-dimensional water motion, ranging from linear theory to fully nonlinear theory, is performed. It is found that for most events the linear theory is sufficient. However, in some cases, more sophisticated theories are needed. Moreover, it is shown that the passive approach in which the seafloor deformation is simply translated to the ocean surface is not always equivalent to the active approach in which the bottom motion is taken into account, even if the deformation is supposed to be instantaneous.Comment: 39 pages, 16 figures; Accepted to Theoretical and Computational Fluid Dynamics. Several references have been adde

    The risk stratification of adverse neonatal outcomes in women with gestational diabetes (STRONG) study

    Get PDF
    Aims: To assess the risk of adverse neonatal outcomes in women with gestational diabetes (GDM) by identifying subgroups of women at higher risk to recognize the characteristics most associated with an excess of risk. Methods: Observational, retrospective, multicenter study involving consecutive women with GDM. To identify distinct and homogeneous subgroups of women at a higher risk, the RECursive Partitioning and AMalgamation (RECPAM) method was used. Overall, 2736 pregnancies complicated by GDM were analyzed. The main outcome measure was the occurrence of adverse neonatal outcomes in pregnancies complicated by GDM. Results: Among study participants (median age 36.8 years, pre-gestational BMI 24.8 kg/m2), six miscarriages, one neonatal death, but no maternal death was recorded. The occurrence of the cumulative adverse outcome (OR 2.48, 95% CI 1.59–3.87), large for gestational age (OR 3.99, 95% CI 2.40–6.63), fetal malformation (OR 2.66, 95% CI 1.00–7.18), and respiratory distress (OR 4.33, 95% CI 1.33–14.12) was associated with previous macrosomia. Large for gestational age was also associated with obesity (OR 1.46, 95% CI 1.00–2.15). Small for gestational age was associated with first trimester glucose levels (OR 1.96, 95% CI 1.04–3.69). Neonatal hypoglycemia was associated with overweight (OR 1.52, 95% CI 1.02–2.27) and obesity (OR 1.62, 95% CI 1.04–2.51). The RECPAM analysis identified high-risk subgroups mainly characterized by high pre-pregnancy BMI (OR 1.68, 95% CI 1.21–2.33 for obese; OR 1.38 95% CI 1.03–1.87 for overweight). Conclusions: A deep investigation on the factors associated with adverse neonatal outcomes requires a risk stratification. In particular, great attention must be paid to the prevention and treatment of obesity
    corecore