Efficient numerical schemes for viscoplastic avalanches. Part 2: the 2D case

This paper deals with the numerical resolution of a shallow water viscoplastic flow model. Viscoplastic materials are characterized by the existence of a yield stress: below a certain critical threshold in the imposed stress, there is no deformation and the material behaves like a rigid solid, but when that yield value is exceeded, the material flows like a fluid. In the context of avalanches, it means that after going down a slope, the material can stop and its free surface has a non-trivial shape, as opposed to the case of water (Newtonian fluid). The model involves variational inequalities associated with the yield threshold: finite volume schemes are used together with duality methods (namely Augmented Lagrangian and Bermúdez–Moreno) to discretize the problem. To be able to accurately simulate the stopping behavior of the avalanche, new schemes need to be designed, involving the classical notion of well-balancing. In the present context, it needs to be extended to take into account the viscoplastic nature of the material as well as general bottoms with wet/dry fronts which are encountered in geophysical geometries. Here we derive such schemes in 2D as the follow up of the companion paper treating the 1D case. Numerical tests include in particular a generalized 2D benchmark for Bingham codes (the Bingham–Couette flow with two non-zero boundary conditions on the velocity) and a simulation of the avalanche path of Taconnaz in Chamonix—Mont-Blanc to show the usability of these schemes on real topographies from digital elevation models (DEM)

Bilateral Asymmetries Assessment in Elite and Sub-Elite Male Futsal Players

This study aimed to investigate morphological, functional, and neuromuscular asymmetries on futsal players’ lower limbs at different competitive levels. Sixteen male elite futsal players from the Spanish National Futsal League and thirteen male sub-elite futsal players from the third division participated in this study. Morphological asymmetry was assessed through bioelectrical impedance (fat-mass (g and %) and lean-mass (g)). Functional asymmetry was assessed by means of a 20-s static unipedal balance test. Finally, neuromuscular asymmetry was assessed using tensiomiography tests on both the rectus femoris (RF) and biceps femoris (BF) of each participant. The three tests conducted did not reveal significant bilateral asymmetries in elite players. On the other hand, sub-elite players showed significant bilateral asymmetry in fat-mass percentage between dominant and non-dominant limbs (+6%; CI95%: 1 to 11; ES: 0.88; p = 0.019). They also showed higher bilateral asymmetry in the delay time of the RF (+13%; CI95%: 7 to 21; ES: 1.3; p 0.05) did not evidence asymmetries regardless of the level of the participants. Elite futsal players do not develop bilateral asymmetries in lower limbs in the studied parameters. On the contrary, sub-elite players are likely to develop morphological and neuromuscular asymmetries between their dominant leg and non-dominant leg.Sin financiación3.390 JCR (2020) Q1, 42/176 Public, Environmental & Occupational Health0.747 SJR (2020) Q2, 50/136 Health, Toxicology and MutagenesisNo data IDR 2020UE

Implementación de balastro con corrección de factor de potencia pasivo

En este documento se analiza funcionamiento de los balastros como fuente de alimentación de lámpara de gases, así como sus diferentes topologías, magnéticas y electrónicas, y la necesidad de usar circuitos de corrección de factor de potencia y disminución de distorsón por armónicos, THD. También se analizó el comportamiento de un balastro ante diferentes etapas de corrección de factor de potencia usando simuladores computacionales como el PSPICE con bases de diseño en un prototipo

New Perspectives on the Optimal Placement of Detectors for Suicide Bombers using Metaheuristics.

Política de acceso abierto tomada de: https://www.springernature.com/gp/open-research/policies/journal-policies y https://beta.sherpa.ac.uk/id/publication/16694We consider an operational model of suicide bombing attacks –an increasingly prevalent form of terrorism– against specific targets, and the use of protective countermeasures based on the deployment of detectors over the area under threat. These detectors have to be carefully located in order to minimize the expected number of casualties or the economic damage suffered, resulting in a hard optimization problem for which different metaheuristics have been proposed. Rather than assum- ing random decisions by the attacker, the problem is approached by considering different models of the latter, whereby he takes informed decisions on which objective must be targeted and through which path it has to be reached based on knowledge on the importance or value of the objectives or on the defensive strategy of the defender (a scenario that can be regarded as an adversarial game). We consider four different algorithms, namely a greedy heuristic, a hill climber, tabu search and an evolutionary algorithm, and study their performance on a broad collection of problem instances trying to resemble different realistic settings such as a coastal area, a modern urban area, and the historic core of an old town. It is shown that the adversarial scenario is harder for all techniques, and that the evolutionary algorithm seems to adapt better to the complexity of the resulting search landscape.Spanish Ministerio de Economı́a and European FEDER under Projects EphemeCH (TIN2014-56494-C4-1-P) and DeepBIO (TIN2017-85727-C4-1-P

A GRASP-based memetic algorithm with path relinking for the far from most string problem.

Política de acceso abierto tomada de: https://www.elsevier.com/about/policies-and-standards/copyrightThe FAR FROM MOST STRING PROBLEM (FFMSP) is a string selection problem. The objective is to find a string whose distance to other strings in a certain input set is above a given threshold for as many of those strings as possible. This problem has links with some tasks in computational biology and its resolution has been shown to be very hard. We propose a memetic algorithm (MA) to tackle the FFMSP. This MA exploits a heuristic objective function for the problem and features initialization of the population via a Greedy Randomized Adaptive Search Procedure (GRASP) metaheuristic, intensive recombination via path relinking and local improvement via hill climbing. An extensive empirical evaluation using problem instances of both random and biological origin is done to assess parameter sensitivity and draw performance comparisons with other state-of-the-art techniques. The MA is shown to perform better than these latter techniques with statistical significance.ANYSELF (TIN2011-28627-C04-01) of MICINN and DNEMESIS (TIC-6083) of Junta de Andalucía

Metaheuristic Approaches to the Placement of Suicide Bomber Detectors.

Suicide bombing is an infamous form of terrorism that is becoming increasingly prevalent in the current era of global terror warfare. We consider the case of targeted attacks of this kind, and the use of detectors distributed over the area under threat as a protective countermeasure. Such detectors are non-fully reliable, and must be strategically placed in order to maximize the chances of detecting the attack, hence minimizing the expected number of casualties. To this end, different metaheuristic approaches based on local search and on population-based search (such as a hill climber, different Greedy randomized adaptive search procedures, an evolutionary algorithm and several estimation of distribution algorithms) are considered and benchmarked against a powerful greedy heuristic from the literature. We conduct an extensive empirical evaluation on synthetic instances featuring very diverse properties. Most metaheuristics outperform the greedy algorithm, and a hill-climber is shown to be superior to remaining approaches. This hill-climber is subsequently subject to a sensitivity analysis to determine which problem features make it stand above the greedy approach, and is finally deployed on a number of problem instances built after realistic scenarios, corroborating the good performance of the heuristic.Spanish Ministry of Economy and Competitiveness and European Regional Development Fund (FEDER) under project EphemeCH (TIN2014-56494-C4-1-P)

El Virus de la Destrucción, o la defensa de lo inútil

Is science and culture a commodity?, Have we transformed what once was sacred –or a symbol of the domination by the religion–, in a new tool for collective control? Is techno-science a field slave of free market to subvert the masses, rather than to generate social significant operations? Film, art, video games, the technical image as it would be called by Vilem Flusser, in relation to Paul Virilio dromology and liquid modernity of Zygmunt Bauman, show a series of techno-political conditions that determine the hybrid military technology and society, where language is a kind of destructive virus, where the useless and the voluntary suspension of logic seem in this context, the only temporary autonomous zones of common sense.¿Es la ciencia y la cultura un bien de consumo?, ¿hemos transformado lo que alguna vez vez fue sagrado –o símbolo de la dominación mediante la religión–, en un nueva herramienta de control colectivo? ¿es la tecno ciencia un campo de acción esclava del libre mercado para subvertir a las masas, mas que para generar operaciones de trascendencia social? Cine, arte, video juegos, la imagen técnica como la llamaría Vilem Flusser, en relación a la dromología de Paul Virilio y a la modernidad liquida de Zygmunt Bauman, evidencianuna serie de condiciones tecnopoliticas que determinan el híbrido tecnología militar y sociedad, donde el lenguaje es una especie de virus de la destrucción, donde lo inútil y la suspensión voluntaria de la lógica parecen en este contexto, las únicas zonas autónomas temporales del sentido común.A ciência e a cultura são bens de consumo? Transformamos aquilo que foi sagradoalguma vez –ou símbolo da dominação mediante a religião– em uma nova ferramentade controle coletivo? É a tecno ciência um campo de ação escrava do livre mercado paraalterar às massas, mas que para gerar operações de transcendência social?Cinema, arte, jogos de vídeo, a imagem técnica como a chamaria Vilem Flusser, em relaçãoà dromologia de Paul Virilio e a modernidade líquida de Zygmunt Bauman, evidenciamuma série de condições tecno-políticas que determinam o híbrido tecnologia militar esociedade, onde a linguagem é como um vírus da destruição, e onde o inútil e a suspensãovoluntária da lógica parecem neste contexto as únicas zonas autônomas temporais dosenso comum

Alteraciones de la cinética del poro de fusión exocitótico en células cromafines de modelos murinos de enfermedades neurodegenerativas

Tesis doctoral inédita leída en la Universidad Autónoma de Madrid, Facultad de Medicina, Departamento de Farmacología. Fecha de lectura: 26-06-201