Comparative assessment of control strategies for the biradial turbine in the Mutriku OWC plant

To be competitive against other renewable energy sources, energy converted from the ocean waves needs to reduce its associated levelised cost of energy. It has been proven that advanced control algorithms can increase power production and device reliability. They act throughout the power conversion chain, from the hydrodynamics of wave absorption to the power take-off to improve the energy yield. The present work highlights the development and test of several algorithms to control the biradial turbine which is to be installed in the Mutriku oscillating water column plant. A collection of adaptive and predictive controllers is explored and both turbine speed controllers and latching strategies are examined. A Wave-to-Wire model of one chamber of the plant is detailed and simulation results of six control laws are obtained. The controllers are then validated using an electrical test infrastructure to prepare the future deployment in the plant. Finally, the control strategies are assessed against criteria like energy production, power quality or reliability.This work has received funding from the European Union'sHorizon 2020 research and innovation programme under grantagreement No 654444 (OPERA Project). This work was financed by GV/EJ (Basque Country Government) under grants IT1324-19. The second author was partially funded by the Portuguese Foundationfor Science and Technology (FCT) through IDMEC, under LAETAPEst-OE/EME/LA0022 by FCT researcher grant No. IF/01457/2014.The authors acknowledge AZTI Tecnalia for wave resource data measured at the plant

Determination of the WYPiWYG strain energy density of skin through finite element analysis of the experiments on circular specimens

[EN] Skin is a biological material which mechanical behavior has large variations depending on the individual and the location of the specimen in that individual, among other factors. Large differences are also encountered in measurements between in vivo and in vitro specimens. Then, optimal characterization of the skin for simulation (for example) of surgical procedures requires that all experiments to characterize the material behavior be performed on the same specimen and in vivo if possible. Recent experiments on circular discs (Groves et al., 2013 [16]) permit this characterization using a single specimen as we show in this paper, and may constitute a good starting point for ulterior characterization in vivo. However, because in these tests deformations are not homogeneous, the determination of the material behavior is not as direct as with tensile or biaxial tests, so finite element analysis is needed to propose a procedure to determine the material behavior. In this work we perform an analysis of the experiments using finite elements obtaining an insight which permits a very simple iterative procedure to determine the stress-strain behavior of the material and, thereafter, the corresponding What-YouPrescribe-Is-What-You-Get (WYPiWYG) stored energy densitiesPartial financial support for this work has been given by grant DPI2015-69801-R from the Direccion General de Proyectos de Investigacion of the Ministerio de Economia y Competitividad of Spain. The ADINA program license used for this work has been a courtesy of ADINA R & D to the Universidad Politecnica de Madrid. FJM also acknowledges the support of the Department of Mechanical and Aerospace Engineering of University of Florida during the sabbatical period in which this paper was completed and Ministerio de Educacion, Cultura y Deporte of Spain for the financial support for that stay under grant PRX15/00065Romero, X.; Latorre, M.; Montáns, FJ. (2017). Determination of the WYPiWYG strain energy density of skin through finite element analysis of the experiments on circular specimens. Finite Elements in Analysis and Design. 134:1-15. https://doi.org/10.1016/j.finel.2017.05.00911513

The relevance of transverse deformation effects in modeling soft biological tissues

[EN] Hyperelastic constitutive models for anisotropic biological materials are frequently based on orthotropic incompressible stored energy functions. The material parameters of these models are then obtained through an optimization procedure as to fit some stress-strain experimental data. For example, in arterial wall mechanics the material data usually employed for the Holzapfel-Gasser-Ogden and the Gasser-Ogden-Holzapfel models are two uniaxial tension curves from circumferential and axial specimens. The transverse strains from these specimens are frequently not taken into consideration. In this paper we analyze the evolution of those strains, showing that an unrealistic behaviour may be predicted. We then show how transverse strains may be prescribed using our What-You-Prescribe-Is-What-You-Get (WYPI-VVYG) model in a very intuitive way, still capturing the longitudinal stress-strain behavior in an exact manner without employing any constitutive parameter. This is possible because, in contrast to what it is usually done, we exactly solve the equilibrium and compatibility equations without imposing the shape of the stored energy function. Furthermore, we show that the small strains formulation is naturally recovered and that the physical insight from the infinitesimal theory is preserved. In fact, for incompressible materials, the present approach can be considered as a natural extension of the infinitesimal continuum elastic framework to large strains. This new physical insight clearly shows that if some subclasses of orthotropic incompressible material models are determined with just two uniaxial curves, then the transverse behavior should be contrasted with additional experimental observations. (C) 2016 Elsevier Ltd. All rights reserved.Partial financial support for this work has been given by grants DPI2011-26635 and DPI2015-69801-R from the Direccion General de Proyectos de Investigacion of the Ministerio de Economia y Competitividad of Spain. F.J. Montans also acknowledges the support of the Department of Mechanical and Aerospace Engineering of University of Florida during the sabbatical period in which part of this work was performed and Ministerio de Educacion, Cultura y Deporte of Spain for the financial suport for that stay under grant PRX15/00065Latorre, M.; Romero, X.; Montáns, FJ. (2016). The relevance of transverse deformation effects in modeling soft biological tissues. International Journal of Solids and Structures. 99:57-70. https://doi.org/10.1016/j.ijsolstr.2016.08.00657709

OS CIRCUITOS ESPACIAIS DA PRODUÇÃO E A INSERÇÃO DE SÃO JOSÉ DO RIO PRETO NA ATUAL DIVISÃO TERRITORIAL DO TRABALHO

The modernizations that have reached the city of São José do Rio Preto, in the northwestern of the state of São Paulo since years 70, make possible the functioning of space circuits of production, whose flows articulate areas and points in the domestic territory and beyond its borders. As result, the urban net becomes more complex and a new situation is established. The logic of regional economy is replaced for the logic of the Brazilian socioespacial formation, in which the city has its functions redefined. Key words: Spatial circuits of production. The city of São José do Rio Preto. Urban net. Region.As modernizações que têm atingido São José do Rio Preto no noroeste paulista desde os anos 70 possibilitam o funcionamento de circuitos espaciais da produção cujos fluxos articulam áreas e pontos de diversas geometrias no território nacional e para além de suas fronteiras. Como resultado, a rede urbana torna-se mais complexa e uma nova situação é estabelecida. A economia regional dá lugar a uma organização territorial produtiva mais complexa em meio a qual a cidade tem sua função redefinida diante da formação socioespacial brasileira. Palavras-chave: Circuitos espaciais da produção. São José do Rio Preto. Rede urbana. Região

Estado de salud dental y gingival de los pacientes internos con trastornos mentales del Hospital Psiquiátrico “José Dolores Fletes Valle” en el año 2014

Los pacientes con trastornos mentales presentan diversas dificultades para apropiarse de técnicas en higiene oral, lo que proporciona un ambiente favorable para el crecimiento de las bacterias oportunistas, las cuales agregadas a las limitaciones en el ámbito de salud oral son factores que inciden directamente en la salud bucal, causándole una serie de problemas de salud como alteraciones periodontal, caries, traumatismos teniendo como resultado la pérdida de piezas dentales. Este estudio plantea determinar el estado de salud oral en los pacientes internos del “Hospital José Dolores Fletes Valles” en el año 2014. Se realizó un estudio descriptivo, observacional de corte transversal basado en la inspección de la cavidad oral y la revisión de expedientes clínicos con un universo de 193 pacientes y una muestra de 129 con una confiabilidad del 95% y un error muestral del 5%, a los cuales se aplicaron los índices epidemiológicos CPOD, índice de placa visible simplificado (IPVS) e índice gingival reducido (IGR). Se determinó que de los 91 pacientes el 91.1% de estos paciente presentan acumulo de placa, el 99.9% presentan experiencia de caries y el 92.3 presentan gingivitis severa. Siendo también el trastorno mental más común esquizofrenia presentándose en el 33% de los pacientes seguido del trastorno orgánico con el 22%. Los resultados de este estudio llevan a concluir que la mayoría los pacientes presentaron la puntación máxima de los índice aplicados, lo que se interpreta como una deficiente salud oral de estos pacientes. Mismas que llevan a recomendar al centro hospitalario mejorar la atención de los paciente

Lugar, Pluralidade da Existência e Democracia

No Brasil, o aprofundamento das políticas neoliberais para atender as demandas das empresas globais, do agronegócio e das finanças tem levado a recuos significativos em relação à soberania nacional e à cidadania. Diante da ausência de um projeto nacional democrático, os espaços de interesse das grandes empresas são modernizados enquanto, consequentemente, é gerada uma desorganização do resto do território e da sociedade, que não interessam ou são residuais para essas políticas. Diante desse fato, urge a proposição de políticas que sejam democráticas, socialmente referenciadas, capazes de se sobrepor a essa lógica perversa. Neste artigo, propomos uma pequena reflexão da importância de se considerar a diversidade dos lugares e de todos os homens, todas as mulheres, instituições e empresas que os coabitam, para pensar e elaborar políticas públicas que levem em conta sujeitos concretos e permitam o uso democrático e plural do território

Soil physico-chemical properties and Organic Carbon stocks across different land use in an urban park of Vilnius, Lithuania

Urban areas are characterised by land use change processes. Urban and peri-urban soils degradation increase at the different land uses, and the characteristic of each land use affecting soil carbon stock and, consequently, the role of soil as a CO2 sink. The aim of this work was to assess the effect of land use and soil management practices in urban and peri-urban soils in Vilnius (Lithuania). Studied properties were: Sand, Clay, Silt, Stoniness, bulk density (BD), pH, electrical conductivity (EC) and soil organic carbon stocks (SOCS). Ten samples were collected at depths 0-10 cm in 8 different land uses and soil management practices in the urban and peri-urban areas of Vilnius. Forests – Quercus robur, Acer plantanoides, Pinus sylvestris and Picea abies, grasslands – semi-natural grasslands (SNG) and managed semi-naturalgrasslands (MSNG), both dominated by Taraxacum officinale, artificial grasslands (AG), and urban. SOC (t/ha) resulted significantly higher in Pinus sylvestris and Art. Grass than in Quercus robur, Acer plantanoides, and urban land uses. Urban land use recorded lower values of SOC (t/ha) than the other land uses except for Acer plantanoides. Land uses with high human intervention decline soil quality and affect the role of soil as a climate regulator

Estimating fuel consumption from radar tracks

Fuel consumption is one of the major considerations for both the impact of aviation in the environment and the cost of operations. This paper assesses the accuracy of a method capable of producing aircraft fuel estimates based on their 4D trajectory and the weather forecast. Fuel consumption estimates generated for 2448 descents are compared with the flight data recorder (FDR) values provided by the airline. Fuel consumption is estimated by taking the 4D trajectory from two different sources: the FDR system itself and surveillance radar tracks. In both cases, the Base of Aircraft Data (BADA) and a model that fits manufacturers’ performance data to polynomial functions are used to represent aircraft performance. Results obtained with the later show that fuel usage could be estimated with an accuracy of 16 kg (4.8%) by using the 4D trajectory as reported by the FDR system and 28 kg (7.8%) by using surveillance radar observations. It is also observed that the BADA 3.6 model underestimates the fuel consumption, illustrating the need for an improved performance model in the terminal manoeuvring area.Peer ReviewedPostprint (published version