26 research outputs found

    Power system stabiliser capability of offshore wind power plants

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    Nowadays, wind power generation is being located offshore because of its higher wind speed at lower height and larger installation zones in comparison with onshore technologies. Recently, the concept of wind power plant has been introduced as a result of the increment of wind power penetration in power systems. Transmission system operators are requiring wind power generation to help to power system with some ancillary services such as fault ride through or power system stabiliser capability. Therefore, it is important to study power system stabiliser capability of wind power plants. In this paper, a comparison of various power system stabiliser schemes is presented. The effect of the distance from the shore tie-line to the offshore wind farm on the controller response is also evaluated. These studies show that offshore wind power plants have promising power system stabiliser capability even using local input signals.Postprint (published version

    An Eulerian-Lagrangian open source solver for bubbly flow in vertical pipes

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    Air-water two-phase flow is present in natural and industrial processes of different nature as nuclear reactors. An accurate local prediction of the boiling flow could support safety and operation analyses of nuclear reactors. A new Eulerian-Lagrangian approach is investigated in this contribution. A new solver has been developed and implemented in the framework of the open source package OpenFOAM R and based on the PIMPLE algorithm coupled with the Lagrangian equation of motion has been implemented for computing incompressible bubbly flows. Each bubble is divided in equivolumetric volumes and tracked into the Eulerian mesh for an appropriate assignment of the effect of the bubble in the cell without resolving the interface. The coupling between phases is done considering in the momentum equation the interfacial forces and bubble induced contribution along the bubble path during an Eulerian time step. The bouncing of the bubbles between themselves and the wall is modeled with a dynamic soft sphere model. The computational results obtained for different flow conditions are validated with the recently released experimental data on upward pipe flow. The test section used is a 52 mm pipe of 5500 mm of length maintained under adiabatic conditions with air and water circulating fluids working with inlet velocity ranges of 0-2 m/s and 0-0.3 m/s for the continuous and dispersed phase respectively. Averaged results of radial distribution for void fraction, chord length, turbulence kinetic energy, dispersed and continuous velocity profiles show a good agreement among different flow conditions.Peña Monferrer, C.; Muñoz-Cobo González, JL.; Monrós Andreu, G.; Martinez Cuenca, R.; Chiva Vicent, S. (2014). An Eulerian-Lagrangian open source solver for bubbly flow in vertical pipes. Sociedad Nuclear Española. http://hdl.handle.net/10251/71943

    Controlled trial of balance training using a video game console in community-dwelling older adults

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    gamification is a potentially attractive option for improving balance and reducing falls. to assess the effect of balance training using the NintendoTM Wii game console on balance (primary outcome), falls and fear of falling. quasi-randomised, open-label, controlled clinical trial in parallel groups, carried out on community-dwelling patients over 70 years, able to walk independently. Participants were assigned 1:1 to the intervention or control group. Balance training was conducted using the Nintendo WiiFit TM twice a week for 3 months. Balance was assessed using the Tinetti balance test (primary outcome), the unipedal stance and the Wii balance tests at baseline, 3 months and 1 year. Falls were recorded and Fear of falling was assessed by the Falls Efficacy Scale (Short-FES-I). 1,016 subjects were recruited (508 in both the intervention and the control group; of whom 274 and 356 respectively completed the 3-month assessment). There was no between-group difference in the Tinetti balance test score, with a baseline mean of 14.7 (SD 1.8) in both groups, and 15.2 (1.3) at 3 months in the intervention group compared to 15.3 (1.7) in controls; the between-group difference was 0.06 (95% CI 0.30-0.41). No differences were seen in any of the other balance tests, or in incident falls. There was a reduction in the fear of falling at 3 months, but no effect at 1 year. the study found no effect of balance training using the Nintendo TM Wii on balance or falls in older community-dwelling patients. The study protocol is available at clinicaltrials.gov under the code NCT02570178

    Añadiendo mecanismos de ayuda en un juez on-line automático para soporte a mentorías académicas

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    Todos los jueces en línea, incluído en sus inicios ¡Acepta el reto! (https://www.aceptaelreto.com) desarrollado por profesores de la UCM, adolecen de un problema de realimentación al usuario: cuando el visitante hace un envío incorrecto el sistema no es capaz de dar información específica del error. El documento es la memoria final de un Proyecto de Innovación y Mejora de la Calidad Docente (PIMCD) de 2017/2018 en el que se puso en marcha un sistema de pistas en el juez

    Impact of a Primary Care Antimicrobial Stewardship Program on Bacterial Resistance Control and Ecological Imprint in Urinary Tract Infections

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    Antimicrobial stewardship programs (ASPs) are a central component in reducing the overprescription of unnecessary antibiotics, with multiple studies showing benefits in the reduction of bacterial resistance. Less commonly, ASPs have been performed in outpatient settings, but there is a lack of available data in these settings. We implemented an ASP in a large regional outpatient setting to assess its feasibility and effectiveness. Over a 5-year post-implementation period, compared to the pre-intervention period, a significant reduction in antibiotic prescription occurred, with a reduction in resistance in E. coli urinary isolates. ASP activities also were found to be cost-effective, with a reduction in medication prescription

    Implicaciones de la diferenciación de las células T en autoinmunidad: análisis y caracterización delos linfocitos B intratímicos

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    Tesis doctoral inédita leída el 10-10-1990 en la Universidad Autónoma de Madrid, Facultad de Medicina, Departamento de Medicin

    Power system stabiliser capability of offshore wind power plants

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    Nowadays, wind power generation is being located offshore because of its higher wind speed at lower height and larger installation zones in comparison with onshore technologies. Recently, the concept of wind power plant has been introduced as a result of the increment of wind power penetration in power systems. Transmission system operators are requiring wind power generation to help to power system with some ancillary services such as fault ride through or power system stabiliser capability. Therefore, it is important to study power system stabiliser capability of wind power plants. In this paper, a comparison of various power system stabiliser schemes is presented. The effect of the distance from the shore tie-line to the offshore wind farm on the controller response is also evaluated. These studies show that offshore wind power plants have promising power system stabiliser capability even using local input signals

    Power system stabiliser capability of offshore wind power plants

    No full text
    Nowadays, wind power generation is being located offshore because of its higher wind speed at lower height and larger installation zones in comparison with onshore technologies. Recently, the concept of wind power plant has been introduced as a result of the increment of wind power penetration in power systems. Transmission system operators are requiring wind power generation to help to power system with some ancillary services such as fault ride through or power system stabiliser capability. Therefore, it is important to study power system stabiliser capability of wind power plants. In this paper, a comparison of various power system stabiliser schemes is presented. The effect of the distance from the shore tie-line to the offshore wind farm on the controller response is also evaluated. These studies show that offshore wind power plants have promising power system stabiliser capability even using local input signals
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