Solving shallow-water systems in 2D domains using Finite Volume methods and multimedia SSE instructions

AbstractThe goal of this paper is to construct efficient parallel solvers for 2D hyperbolic systems of conservation laws with source terms and nonconservative products. The method of lines is applied: at every intercell a projected Riemann problem along the normal direction is considered which is discretized by means of well-balanced Roe methods. The resulting 2D numerical scheme is explicit and first-order accurate. In [M.J. Castro, J.A. García, J.M. González, C. Pares, A parallel 2D Finite Volume scheme for solving systems of balance laws with nonconservative products: Application to shallow flows, Comput. Methods Appl. Mech. Engrg. 196 (2006) 2788–2815] a domain decomposition method was used to parallelize the resulting numerical scheme, which was implemented in a PC cluster by means of MPI techniques.In this paper, in order to optimize the computations, a new parallelization of SIMD type is performed at each MPI thread, by means of SSE (“Streaming SIMD Extensions”), which are present in common processors. More specifically, as the most costly part of the calculations performed at each processor consists of a huge number of small matrix and vector computations, we use the Intel© Integrated Performance Primitives small matrix library. To make easy the use of this library, which is implemented using assembler and SSE instructions, we have developed a C++ wrapper of this library in an efficient way. Some numerical tests were carried out to validate the performance of the C++ small matrix wrapper. The specific application of the scheme to one-layer Shallow-Water systems has been implemented on a PC’s cluster. The correct behavior of the one-layer model is assessed using laboratory data

IFCP Riemann solver: Application to tsunami modelling using GPUs

In this work, we present a simplified two-layer model of Savage-Hutter type to simulate tsunamis generated by landslides (see (Fern´andez et al. 2008)). A layer composed of fluidized granular material is assumed to flow within an upper layer composed of an inviscid fluid (e.g. water). The sediment layer ismodelled by a Savage-Hutter type model where buoyancy effects have been considered. The system is discretized using IFCP finite volume scheme. The first order IFCP scheme was introduced in (Fern´andez et al. 2011) and it is constructed by using a suitable decomposition of a Roe matrix by means of a parabolic viscosity matrix, that captures information of the intermediate fields (Intermediate Field Capturing Parabola). Its extension to high order and two-dimensional domains is straightforward. To conclude, some numerical examples are presente

Modelado de Tsunamis en el Mar de Alborán generados por Deslizamientos Submarinos

En este trabajo se estudia el desarrollo de tsunamis en el Mar de Alborán generados por deslizamientos submarinos, ítem que no había sido analizado previamente. En esta cuenca se han descrito deslizamientos de distinta entidad que afectan tanto a sus márgenes como a los taludes de las principales elevaciones morfológicas. El desarrollo de estos procesos de inestabilidad está controlado por la actividad tectónica que ha generado relieves positivos, cuyos taludes están sometidos a la gravedad, y que está produciendo una continúa actividad sísmica que debilita la resistencia de los materiales sedimentarios. El análisis de un mosaico de batimetría multihaz en la Dorsal de Alborán ha permitido localizar un conjunto de cuerpos sedimentarios relacionados con movimientos en masa, que incluyen deslizamientos y sistemas de cañón-abanico. El sistema de cañón-abanico Al-Borani, localizado en el flanco meridional, se ha utilizado para simular numéricamente el tren de olas que generaría al desplazarse desde el talud de la dorsal hasta la Cuenca Meridional. Este modelo ha permitido observar su propagación, la influencia de los rasgos fisiográficos, y las características del tsunami al impactar sobre las costas. El tsunami obtenido del modelo tarda 12 minutos en alcanzar las costas del norte de África (Cabo Tres Forcas) con una altura de 1.5 m, mientras que el primer impacto sobre las costas del sur de la península Ibérica se produciría a los 26 minutos, en la zona de Adra, con una altura de ola de 1 m

Deslizamientos submarinos y tsunamis en el Mar de Alborán. Un ejemplo de modelización numérica

Los componentes principales de este libro son: a) conocer y estudiar determinados fenómenos naturales de consecuencias catastróficas, como los tsunamis, y b) identificar los útiles científicos para representar estos fenómenos. Por ello, es necesario disponer de un profundo conocimiento del fondo marino donde se produce el fenómeno, conocimiento que proviene del análisis de datos geológicos y geofísicos, y por otro lado, es encesario hacer uso de la potencialidad de los modelos matemáticos que permiten realizar simulaciones numéricas precisas. El libro presenta los resultados de la simulación numérica de un tsunami generado en la cuenca del Mar de Alborán y su propagación e interacción con la morfología submarina de dicho área geográfica.Versión del edito

7th Drug hypersensitivity meeting: part two

No abstract availabl

Risk profiles and one-year outcomes of patients with newly diagnosed atrial fibrillation in India: Insights from the GARFIELD-AF Registry.

BACKGROUND: The Global Anticoagulant Registry in the FIELD-Atrial Fibrillation (GARFIELD-AF) is an ongoing prospective noninterventional registry, which is providing important information on the baseline characteristics, treatment patterns, and 1-year outcomes in patients with newly diagnosed non-valvular atrial fibrillation (NVAF). This report describes data from Indian patients recruited in this registry. METHODS AND RESULTS: A total of 52,014 patients with newly diagnosed AF were enrolled globally; of these, 1388 patients were recruited from 26 sites within India (2012-2016). In India, the mean age was 65.8 years at diagnosis of NVAF. Hypertension was the most prevalent risk factor for AF, present in 68.5% of patients from India and in 76.3% of patients globally (P < 0.001). Diabetes and coronary artery disease (CAD) were prevalent in 36.2% and 28.1% of patients as compared with global prevalence of 22.2% and 21.6%, respectively (P < 0.001 for both). Antiplatelet therapy was the most common antithrombotic treatment in India. With increasing stroke risk, however, patients were more likely to receive oral anticoagulant therapy [mainly vitamin K antagonist (VKA)], but average international normalized ratio (INR) was lower among Indian patients [median INR value 1.6 (interquartile range {IQR}: 1.3-2.3) versus 2.3 (IQR 1.8-2.8) (P < 0.001)]. Compared with other countries, patients from India had markedly higher rates of all-cause mortality [7.68 per 100 person-years (95% confidence interval 6.32-9.35) vs 4.34 (4.16-4.53), P < 0.0001], while rates of stroke/systemic embolism and major bleeding were lower after 1 year of follow-up. CONCLUSION: Compared to previously published registries from India, the GARFIELD-AF registry describes clinical profiles and outcomes in Indian patients with AF of a different etiology. The registry data show that compared to the rest of the world, Indian AF patients are younger in age and have more diabetes and CAD. Patients with a higher stroke risk are more likely to receive anticoagulation therapy with VKA but are underdosed compared with the global average in the GARFIELD-AF. CLINICAL TRIAL REGISTRATION-URL: http://www.clinicaltrials.gov. Unique identifier: NCT01090362

Reducing the environmental impact of surgery on a global scale: systematic review and co-prioritization with healthcare workers in 132 countries

Background Healthcare cannot achieve net-zero carbon without addressing operating theatres. The aim of this study was to prioritize feasible interventions to reduce the environmental impact of operating theatres. Methods This study adopted a four-phase Delphi consensus co-prioritization methodology. In phase 1, a systematic review of published interventions and global consultation of perioperative healthcare professionals were used to longlist interventions. In phase 2, iterative thematic analysis consolidated comparable interventions into a shortlist. In phase 3, the shortlist was co-prioritized based on patient and clinician views on acceptability, feasibility, and safety. In phase 4, ranked lists of interventions were presented by their relevance to high-income countries and low–middle-income countries. Results In phase 1, 43 interventions were identified, which had low uptake in practice according to 3042 professionals globally. In phase 2, a shortlist of 15 intervention domains was generated. In phase 3, interventions were deemed acceptable for more than 90 per cent of patients except for reducing general anaesthesia (84 per cent) and re-sterilization of ‘single-use’ consumables (86 per cent). In phase 4, the top three shortlisted interventions for high-income countries were: introducing recycling; reducing use of anaesthetic gases; and appropriate clinical waste processing. In phase 4, the top three shortlisted interventions for low–middle-income countries were: introducing reusable surgical devices; reducing use of consumables; and reducing the use of general anaesthesia. Conclusion This is a step toward environmentally sustainable operating environments with actionable interventions applicable to both high– and low–middle–income countries

Palaeo-tsunamis in glaciated margins from submarine landslides: the case of Storfjorden glacial Fan (SW of the Svalbard Archipelago)

X Congreso Geológico de España, 5-7 de julio 2021, Vitoria-Gasteiz.-- 1 page[EN] The Storfjorden Trough Mouth Fan is affected by a huge submarine landslide mapped based on multibeam bathymetry and very high-resolution seismic profiles. The Storfjorden landslide covers an area of 1200 km2 with a volume of 40 km3. The Landslide-HySEA numerical modelling has simulated the hypothetical tsunami (Gonzalez-Vida et al., 2019). The model related landslide evidences the presence of two interacting sediment volumes, which are slumping simultaneously. Wave trains values are one meter with N-S propagation direction and run-up value ~ 2m in Spitsbergen and Bear Islands. Sedimentary instability would be related to i) the interplay between the over-steeping of the continental slope (4º), ii) the high sedimentation rates of clays during interglacial periods, which are intercalated with glaciogenic sediments deposited during the glacial periods building a stratigraphy with over-consolidated clay levels, iii) and the seismic activity (Faleide et al, 1996). It contributes to increase the knowledge and the evaluation about the potential tsunamigenic of submarine landslides in similar scenarios, where the environmental changes by impact of climatic changes may favour submarine landslide triggering[ES] El abanico de Storfjorden está afectado por un gran deslizamiento submarino identificado en la batimetría multihaz y perfiles sísmicos de muy alta resolución. El deslizamiento de Storfjorden cubre un área de 1200 km2 con un volumen de 40 km 3. Se ha realizado la simulación del deslizamiento mediante el modelo numérico Landslide-HySEA (González-Vida et al., 2019). El análisis del deslizamiento proporciona evidencia de la presencia de dos volúmenes de sedimentos interactivos, que se desploman simultáneamente. El tsunami comprende trenes de olas de 1 m de amplitud que se dispersan hacia N-S, afectando las costas de Spitsbergen y la Isla del Oso con olas ~ 2 m. La inestabilidad sedimentaria que desencadena el tsunami podría estar relacionada con varios factores: i) las pendientes del talud (4º); ii) la rápida deposición de arcillas durante los periodos inter-glaciares alternados con sedimentos glaciogénicos en eventos glaciares, favoreciendo la sub-consolidación de las arcillas; y iii) la ocurrencia de terremotos (Faleide et al, 1996). Ello contribuye al estudio y evaluación del potencial tsunamigénico de deslizamientos submarinos en escenarios similares, donde los cambios ambientales debido al impacto del cambio climático pueden favorecer el desarrollo de procesos de inestabilidad sedimentaria submarinaPeer reviewe

Tsunamigenic risk associated to vertical offset in transcurrent fault termination (Westernmost Mediterranean)

European Geosciences Union (EGU) General Assembly, 7-12 April 2019, Vienna, Austria.-- 1 pageThe Mediterranean Sea has one of the longest records of tsunami and represents the 10.1 percentage distribution of tsunami in the world’s oceans and seas. The Alboran Basin (Westernmost Mediterranean) is tectonically active as it is suggested by recent earthquakes triggered by several faults, mostly located in the central zone, and formed due to the tectonic indentation in a context of convergence between Africa and Eurasia plates. One of these active faults is the Averroes fault, a NW-SE dextral transcurrent structure with vertical offset at its termination, which is analysed to test its tsunamigenic potentiality. While the propagation of tsunamis by normal or reverse faults is well simulated by numerical models, those generated by structures as the Averroes fault, has not received the interest of the scientific community attention. Through a multidisciplinary approach that involves morphological, seismic stratigraphy, and physical and numerical modellings, we test the generation of tsunamis or the subsequent inundation by the Averroes fault. The bathymetric and seismic analysis point to the Averroes fault has a maximum vertical offset of 5.4 m. The crustal deformation at the sea bottom surface generated by a given earthquake hosted in the Averroes Fault has been computed using the Coulomb 3.3 code, where calculations are done using the Okada’s 1992 approach, assuming an elastic halfspace with uniform elastic properties. Computed deformation pattern is characterized by an uplifting lobe (footwall block) and a subsiding lobe (hanging wall block). The Mw for this event is 7.03. The tsunami wave propagation generated by the seafloor deformation has been modelized with the Tsunami-HySEA (HySEA stands for Hyperbolic Systems and Efficient Algorithms). The tsunami modelling shows three main wave fronts directed towards the NW, NE and S, being the most affected areas the Campo de Dalias (Almeria) and Malaga, located to the north of the Averroes Fault in the Spanish coast. The maximum wave heights reach about 3 m in the Averroes fault area, and about 2.5 m in the Campo de Daliasand Malaga coasts. The time arrivals are 15’ for the first case and about 25’ for the last.The results of this work contribute to increase the number of tsunamigenic sources to be considered in the Alboran Sea. Although transcurrent structures have not been considered by their kinematics as potential triggers of tsunamis, here we demonstrate that the vertical offset at their terminations may generate destructive tsunamis. In addition, in the case of the Alboran Sea, those tsunamis would represent rapid-onset hazards, with time arrivals too short for alert systems, in a densely populated coast that increases during tourist arrivals during the spring and summer periods. This study also highlights the need to review the tsunamigenic potential hazards for similar strike-slip faults with vertical offsets in other seas and ocean