117 research outputs found

    Smart grids for rural conditions and e-mobility - Applying power routers, batteries and virtual power plants

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    Significant reductions of greenhouse gas emission by use of renewable energy sources belong to the common targets of the European Union. Smart grids address intelligent use and integration of conventional and renewable generation in combination with controllable loads and storages. Two special aspects have also to be considered for smart grids in future: rural conditions and electric vehicles. Both, the increasing share of renewable energy sources and a rising demand for charging power by electrical vehicles lead to new challenges of network stability (congestion, voltage deviation), especially in rural distribution grids. This paper describes two lighthouse projects in Europe (“Well2Wheel” and “Smart Rural Grid”) dealing with these topics. The link between these projects is the implementation of the same virtual power plant technology and the approach of cellular grid cells. Starting with an approach for the average energy balance in 15 minutes intervals in several grid cells in the first project, the second project even allows the islanded operation of such cells as a microgrid. The integration of renewable energy sources into distribution grids primary takes place in rural areas. The lighthouse project “Smart Rural Grid”, which is founded by the European Union, demonstrates possibilities to use the existing distribution system operator infrastructure more effectively by applying an optimised and scheduled operation of the assets and using intelligent distribution power routers, called IDPR. IDPR are active power electronic devices operating at low voltage in distribution grids aiming to reduce losses due to unbalanced loads and enabling active voltage and reactive power control. This allows a higher penetration of renewable energy sources in existing grids without investing in new lines and transformers. Integrated in a virtual power plant and combined with batteries, the IDPR also allows a temporary islanded mode of grid cells. Both projects show the potential of avoiding or postponing investments in new primary infrastructure like cables, transformers and lines by using a forward-looking operation which controls generators, loads and batteries (mobile and stationary) by using new grid assets like power routers. While primary driven by physical restrictions as voltage-band violations and energy balance, these cells also define and allow local smart markets. In consequence the distribution system operators could avoid direct control access by giving an incentive to the asset owners by local price signals according to the grid situation and forecasted congestions.Peer ReviewedPostprint (published version

    ¿Hacia la adquisición de competencias con actividades MBL?

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    La distribución a los centros de Cataluña de los equipamientos necesarios ha contribuido a un cierto desarrollo en la utilización de sistemas de captación de datos (MBL) en las aulas de secundaria. Los datos de los que se dispone sugieren que la utilización del equipamiento por parte del profesorado de secundaria es baja a pesar de haberse proporcionado ocasiones para la formación. Una de las posibles causas de esta situación puede ser la falta de reflexión sobre como deberían ser diseñadas las actividades con MBL para favorecer la adquisición de competencias científicas, así como cuál debería ser la gestión del aula para conseguir un aprendizaje más eficaz. En esta comunicación presentaremos los aspectos que, a partir de nuestra experiencia como formadoras y como participantes en el proyecto Comenius The effective use of ICT in science education, creemos tendrían que ser tenidos en cuenta a la hora de planificar actividades con MBL

    Classical and quantum ergodicity on orbifolds

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    We extend to orbifolds classical results on quantum ergodicity due to Shnirelman, Colin de Verdi\`ere and Zelditch, proving that, for any positive, first-order self-adjoint elliptic pseudodifferential operator P on a compact orbifold X with positive principal symbol p, ergodicity of the Hamiltonian flow of p implies quantum ergodicity for the operator P. We also prove ergodicity of the geodesic flow on a compact Riemannian orbifold of negative sectional curvature.Comment: 14 page

    The early Miocene lake of Foieta la Sarra-A in eastern Iberian Peninsula and its relevance for the reconstruction of the Ribesalbes-Alcora Basin palaeoecology

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    The Ribesalbes-Alcora Basin (Castelló Province, Spain) contains two lower Miocene units that are rich in fossils. The Unit B contains oil-shale and laminated bituminous dolomicrite related to a palaeolake, whereas the Unit C is composed of sandstone and mudstone beds from distal deltaic and shallow lacustrine environments. The La Rinconada and San Chils localities from the Unit B have yielded a fossil assemblage of plants, molluscs, arthropods, and vertebrates, while the localities from the Unit C in the Campisano ravine (Araia/Mas d'Antolino outcrop) are rich in mammalian record. Here we study a new palaeolake deposit of laminated lacustrine limestone beds in the Unit C named Foieta la Sarra-A. This new locality has provided an assemblage of charophytes, terrestrial plants, molluscs, arthropods, and teleosteans. The latter represent the only known fish record from the Ribesalbes-Alcora Basin to date. Although the specimens are generally poorly preserved, the presence of soft-body preservation due to the action of microbial mats at the lake bottom allows considering the Foieta la Sarra-A locality as a Konservat-Lagerstätte. The Foieta la Sarra-A palaeolake had a different water chemistry compared to that represented in the Unit B. Its depth was about a few metres and the water level suffered periodic fluctuations. This new locality sheds light on the palaeoenvironmental dynamics of the Ribesalbes-Alcora Basin during the early Miocene and provides a new approach to the palaeoecological reconstruction of the basin

    Language therapy effects on the treated and untreated languages of a multilingual person with aphasia

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    We administered language treatment in the first language of a multilingual person with aphasia and tested his skills pre- and post-treatment in his additional languages. We report improvement in object and action naming in the treated language (Catalan, the participant’s L1). Small cross-language generalization was found for Spanish, his highly-proficient, early-acquired, L2 as well as for English, his least-proficient language. Improvement was noted not only in items that were translation-equivalents of trained items but also of untrained items. Cognate status did not seem to influence the results

    Children's Health Habits and COVID-19 Lockdown in Catalonia : Implications for Obesity and Non-Communicable Diseases

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    Lockdown during the COVID-19 pandemic imposed changes in children's daily routine that could lead to changes in behavior patterns. Using a survey targeted at children under 17 years of age, we described dietary (adherence to Mediterranean diet, AMD) and sleeping habits (disorders of initiating and maintaining sleep) after the implementation of lockdown, and examined the probability of the inadequate frequency of physical activity (PA) and use of TV and electronic devices (TV-ED) before and after lockdown through generalized estimating equation models, accounting for age and gender differences. From 3464 children included, 53.2% showed optimal AMD; 79.2% referred to delayed bedtime; and 16.3% were suspected of sleeping disorders after the implementation of lockdown. Delay in bedtime was more frequent among children older than 6 years, and inadequate sleeping hours among those younger than 11 years. There were no gender differences in AMD or sleeping habits. The odds of inadequate frequency of PA and TV-ED use were greater after lockdown, with a greater risk for TV-ED use. Boys were at greater risk of inadequate PA frequency and TV-ED use. Odds ratio of inadequate PA was greater at older ages. Lockdown could influence changes in children's habits that could lead to risk factors for non-communicable diseases during adulthood if such behaviors are sustained over time

    Voz del anciano

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    La vejez es en sí un fenómeno biológico que no implica necesariamente una enfermedad. Los fenómenos biológicos del envejecimiento se inician en edades muy tempranas y tiene la capacidad de modificarse, preveerse y compensarse. La educación y la preparación para posibles deterioros debe de ser contemplada desde un plano preventivo. En el ser humano la aparición del lenguaje y su vehículo habitual, la voz; representó la posibilidad de aumentar su longevidad. El deterioro vocal del anciano se conoce como presbifonía y en ocasiones interfiere significativamente en la capacidad de comunicación y en la calidad de vida de las personas ancianas. Al considerar la presbifonía o voz senil hay que distinguir dos situaciones clínicas distintas desde el punto de vista conceptual: la disfonía del anciano y la disfonía en el anciano. Se comentan los aspectos del envejecimiento en relación con la voz, la valoración y la caracterización de la voz en el anciano y las estrategias para prevenir el deterioro y tratar los trastornos específicos de la voz en las personas mayores, bien sea desde el punto de vista funcional o rehabilitación o bien mediante cirugía

    Los seminarios de innovación en ciencias en Cataluña : un modelo de formación basado en la práctica reflexiva

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    El Programa de formación en ciencias para la ESO en Cataluña se inició en el curso 2003-04. Durante los cursos 2004-05 y 2005-06 se realizaron cursos de formación que intentaban promover nuevas maneras de enseñar ciencias a partir de la presentación de secuencias didácticas contextualizadas y la elaboración y experimentación de mini-secuencias similares por parte de los profesores participantes. En el curso 2006-07 el programa sufre un cambio de enfoque, adoptando un modelo de formación basado en la reflexión sobre la propia práctica. La presente comunicación describe las bases de este nuevo enfoque, los Seminarios de Innovación en Ciencias realizados y los resultados obtenidos en los dos últimos cursos

    JavaCyte, a novel open-source tool for automated quantification of key hallmarks of cardiac structural remodeling

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    Many cardiac pathologies involve changes in tissue structure. Conventional analysis of structural features is extremely time-consuming and subject to observer bias. The possibility to determine spatial interrelations between these features is often not fully exploited. We developed a staining protocol and an ImageJ-based tool (JavaCyte) for automated histological analysis of cardiac structure, including quantification of cardiomyocyte size, overall and endomysial fibrosis, spatial patterns of endomysial fibrosis, fibroblast density, capillary density and capillary size. This automated analysis was compared to manual quantification in several well-characterized goat models of atrial fibrillation (AF). In addition, we tested inter-observer variability in atrial biopsies from the CATCH-ME consortium atrial tissue bank, with patients stratified by their cardiovascular risk profile for structural remodeling. We were able to reproduce previous manually derived histological findings in goat models for AF and AV block (AVB) using JavaCyte. Furthermore, strong correlation was found between manual and automated observations for myocyte count (r = 0.94, p < 0.001), myocyte diameter (r = 0.97, p < 0.001), endomysial fibrosis (r = 0.98, p < 0.001) and capillary count (r = 0.95, p < 0.001) in human biopsies. No significant variation between observers was observed (ICC = 0.89, p < 0.001). We developed and validated an open-source tool for high-throughput, automated histological analysis of cardiac tissue properties. JavaCyte was as accurate as manual measurements, with less inter-observer variability and faster throughput

    Turnos de 7 horas versus 12 horas en enfermería intensiva: vivir a contratiempo

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    Resumen Los turnos de trabajo tienen repercusión sobre el bienestar de los profesionales sanitarios influyendo en su calidad de vida. El objetivo principal de este estudio es describir las consecuencias que tiene el turno de trabajo diurno de 12 h respecto al de 7 h en los profesionales de enfermería que trabajan en Unidades de Cuidados Intensivos. Se trata así de un estudio descriptivo transversal en 2 hospitales de tercer nivel de Barcelona: Hospital Clínico y Hospital Vall d"Hebron (turnos de 7 h y 12 h respectivamente). La recogida de datos se ha realizado mediante cuestionario ad hoc de 29 preguntas cerradas, anónimo y autoadministrado, basado en 2 escalas: Standard Shiftwork Index y Shiftwork locus of control. Dichos datos fueron procesados a través del programa SPSS V.18.0. De las 85 encuestas realizadas 52 fueron válidas: 22 en el Hospital Clínico de Barcelona y 30 en el Hospital Vall d"Hebron. Cabe destacar que los profesionales encuestados que trabajan en turno de 12 h expresan niveles superiores de conciliación laboral y personal, concretamente en tiempo de ocio a disfrutar (× 2: 10,635; p = 0,031) y tiempo de dedicación familia-amigos, así como niveles más bajos de percepción de fatiga. No se han encontrado diferencias entre el tipo de turno y facilidad de desarrollo del trabajo profesional, a pesar de que el turno de 12 h presenta niveles más altos
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