202 resultados para Elorriaga, Joseba
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A 3-year Project started on November 1 2010, financed by the European Commision within the FP-7 Space Program, and aimed at developing an efficient de-orbit system that could be carried on board by future spacecraft launched into LEO, will be presented. The operational system will deploy a thin uninsulated tape-tether to collect electrons as a giant Langmuir probe, using no propellant/no power supply, and generating power on board. This project will involve free-fall tests, and laboratory hypervelocity-impact and tether-current tests, and design/Manufacturing of subsystems: interface elements, electric control and driving module, electron-ejecting plasma contactor, tether-deployment mechanism/end-mass, and tape samples. Preliminary results to be presented involve: i) devising criteria for sizing the three disparate tape dimensions, affecting mass, resistance, current-collection, magnetic self-field, and survivability against debris itself; ii) assessing the dynamical relevance of tether parameters in implementing control laws to limit oscillations in /off the orbital plane, where passive stability may be marginal; iii) deriving a law for bare-tape current from numerical simulations and chamber tests, taking into account ambient magnetic field, ion ram motion, and adiabatic electron trapping; iv) determining requirements on a year-dormant hollow cathode under long times/broad emission-range operation, and trading-off against use of electron thermal emission; v) determining requirements on magnetic components and power semiconductors for a control module that faces high voltage/power operation under mass/volume limitations; vi) assessing strategies to passively deploy a wide conductive tape that needs no retrieval, while avoiding jamming and ending at minimum libration; vii) evaluating the tape structure as regards conductive and dielectric materials, both lengthwise and in its cross-section, in particular to prevent arcing in triple-point junctions.
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As a fundamental contribution to limiting the increase of debris in the Space environment, a three-year project started on 1 November 2010 financed by the European Commission under the FP-7 Space Programme. It aims at developing a universal system to be carried on board future satellites launched into low Earth orbit (LEO), to allow de-orbiting at end of life. The operational system involves a conductive tape-tether left bare of insulation to establish anodic contact with the ambient plasma as a giant Langmuir probe. The project will size the three disparate dimensions of a tape for a selected de-orbit mission and determine scaling laws to allow system design for a general mission. It will implement control laws to restrain tether dynamics in/off the orbital plane; and will carry out plasma chamber measurements and numerical simulations of tether-plasma interaction. The project also involves the design and manufacturing of subsystems: electron-ejecting plasma contactors, an electric control and power module, interface elements, tether and deployment mechanisms, tether tape/end-mass as well as current collection plus free-fall, and hypervelocity impact tests.
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A 3-year Project financed by the European Commission is aimed at developing a universal system to de-orbit satellites at their end of life, as a fundamental contribution to limit the increase of debris in the Space environment. The operational system involves a conductive tapetether left bare to establish anodic contact with the ambient plasma as a giant Langmuir probe. The Project will size the three disparate dimensions of a tape for a selected de-orbit mission and determine scaling laws to allow system design for a general mission. Starting at the second year, mission selection is carried out while developing numerical codes to implement control laws on tether dynamics in/off the orbital plane; performing numerical simulations and plasma chamber measurements on tether-plasma interaction; and completing design of subsystems: electronejecting plasma contactor, power module, interface elements, deployment mechanism, and tether-tape/end-mass. This will be followed by subsystems manufacturing and by currentcollection, free-fall, and hypervelocity impact tests.
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The purpose of this paper is to conduct a review of studies on cystoid macular edema published in the last seven years. Cystoid macular edema is a major cause of loss of visual acuity. It is the final common pathway of many diseases and can be caused by numerous processes including inflammatory, vascular, adverse drug reactions, retinal dystrophy or intraocular tumors. These processes disrupt the blood-retinal barrier, with fluid extravasation to the macular parenchyma. Imaging tests are essential for both detection and monitoring of this pathology. Fluorescein angiography and autofluorescence show the leakage of liquid from perifoveal vessels into the tissue where it forms cystic spaces. Optical coherence tomography is currently the gold standard technique for diagnosis and monitoring. This allows objective measurement of retinal thickness, which correlates with visual acuity and provides more complete morphological information. Based on the underlying etiology, the therapeutic approach can be either surgical or medical with anti-inflammatory drugs. We found that disruption of the blood-retinal barrier for various reasons is the key point in the pathogenesis of cystoid macular edema, therefore we believe that studies on its treatment should proceed on this path.
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Introducción. El cáncer de cuello de útero (CCU), segunda causa de mortalidad por cáncer en mujeres, está asociado a la infección por virus de papiloma humano (VPH), cuya máxima prevalencia se sitúa entre los 20 y 24 años de edad. Desde 2006 se dispone de una vacuna contra el VPH. El objetivo de este estudio es evaluar los conocimientos sobre CCU, la infección por VPH y su vacuna, valorando su aceptabilidad en población universitaria. Métodos. Estudio transversal sobre 1.750 estudiantes de la Universidad de Alicante (2008) seleccionados al azar, proporcional por sexo y estudios, mediante un cuestionario ad-hoc validado. Se calcularon porcentajes, intervalos de confianza, tablas de contingencia según sexo, edad y tipo de estudios, calculando odds ratios ajustadas (OR). Resultados. Muestra con 58,6% mujeres y 6,6% de estudiantes biosanitarios. Un 87,3% dispuestos a vacunarse frente al VPH, el 94,3% vacunaría a sus hijas, un 48,0% había oído hablar de la vacuna. El 90,6% tiene bajos conocimiento sobre la infección por VPH y un 82,2% sobre la vacuna. Un 22,4% manifiesta conocer la asociación entre VPH y CCU. Las mujeres registran OR mayores en conocimientos y predisposición a vacunarse. La aceptabilidad de la vacuna contra VPH se asocia con el sexo y la confianza en las vacunas como método preventivo, la influencia de los conocimientos previos es escasa sobre la predisposición vacunal. Conclusiones. Alta aceptabilidad de la vacuna en el periodo estudiado. Aumentar la confianza hacia las vacunas puede influir en una mejor predisposición a vacunarse.
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Las relaciones públicas se configuran como una actividad esencial en la gestión de la comunicación con los públicos de los clubes de fútbol ya que son muy activos y su grado de reactividad es alto. Con este texto se analiza el papel que desempeñan las redes sociales en los clubes de fútbol que poseen mayor número de ingresos. Para ello, se desarrolla una metodología que estudia qué presencia tienen en las redes sociales, el número de seguidores, qué grado de interacción se produce entre clubes y públicos y los contenidos y las temáticas de los textos de las redes sociales. Los resultados muestran un público activo pero con intervenciones relacionadas con los resultados futbolísticos y una gestión comunicativa unidireccional por parte de los clubes.
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Since its excavation in the summer of 1973, El Niño cave has been considered a key site to understand the process of production economy and pottery technology introduction in South-eastern Iberian Peninsula, and especially to approach how such process could have affected people already settled in the Segura mountains. However, data from El Niño cave was very fragmentary, due to the lack of a broad study of Neolithic occupations of the site. In this paper, we present the analysis of pottery, lithic industry and faunal remains, as well as the existing dates from the site´s Holocene levels. The review of different evidence from the site allows suggesting that El Niño cave would have probably acted as a hunting and shepherding station, being a logistical site of larger places. However, limitations due to the fact that we are dealing with a 40- year-old excavation, prevent specifying how the process of Neolithic introduction in the Segura Mountains occurred.
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Investigación teórica y práctica sobre la aplicación de las alternativas extra-penitenciarias, en concreto entorno a los pisos de acogida para personas privadas de libertad. Se argumenta el marco criminológico en aras de alcanzar una reinserción social óptima del individuo preso.
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Este trabajo tiene como finalidad evidenciar la relación entre la Documentoscopia y la Criminología. Con este fin, se ofrece una visión general de las bases, métodos y técnicas utilizados en la documentoscopia para el análisis de todo tipo de documentos y escritos y para ello, también se ofrecen algunos de los ejemplos prácticos llevados a cabo durante el prácticum del grado.
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322 p.
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El presente proyecto tiene como objetivo la realización de un estudio térmico y acústico de diferentes tipos de fachada multicapa con elementos de madera. De este modo, se analizará el espesor mínimo de aislamiento de las fachadas planteadas con el fin de obtener unas soluciones con el menor espesor posible que cumplan la normativa vigente en el CTE para el mejor aprovechamiento de la superficie útil. Así, será posible conocer diferentes tipologías de fachadas que presenten unas prestaciones térmicas y acústicas idóneas en las distintas zonas climáticas del país, junto con una comparativa económica de las distintas soluciones propuestas.
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Background and objective: Participation in colorectal cancer (CRC) screening varies widely among different countries and different socio-demographic groups. Our objective was to assess the effectiveness of three primary-care interventions to increase CRC screening participation among persons over the age of 50 years and to identify the health and socio-demographic-related factors that determine greater participation. Methods: We conducted a randomized experimental study with only one post-test control group. A total of 1,690 subjects were randomly distributed into four groups: written briefing; telephone briefing; an invitation to attend a group meeting; and no briefing. Subjects were evaluated 2 years post-intervention, with the outcome variable being participation in CRC screening. Results: A total of 1,129 subjects were interviewed. Within the groups, homogeneity was tested in terms of socio-demographic characteristics and health-related variables. The proportion of subjects who participated in screening was: 15.4% in the written information group (95% confidence interval [CI]: 11.2-19.7); 28.8% in the telephone information group (95% CI: 23.6-33.9); 8.1% in the face-to-face information group (95% CI: 4.5-11.7); and 5.9% in the control group (95% CI: 2.9-9.0), with this difference proving statistically significant (p < 0.001). Logistic regression showed that only interventions based on written or telephone briefing were effective. Apart from type of intervention, number of reported health problems and place of residence remained in the regression model. Conclusions: Both written and telephone information can serve to improve participation in CRC screening. This preventive activity could be optimized by means of simple interventions coming within the scope of primary health-care professionals.
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Composition methods are useful when solving Ordinary Differential Equations (ODEs) as they increase the order of accuracy of a given basic numerical integration scheme. We will focus on sy-mmetric composition methods involving some basic second order symmetric integrator with different step sizes [17]. The introduction of symmetries into these methods simplifies the order conditions and reduces the number of unknowns. Several authors have worked in the search of the coefficients of these type of methods: the best method of order 8 has 17 stages [24], methods of order 8 and 15 stages were given in [29, 39, 40], 10-order methods of 31, 33 and 35 stages have been also found [24, 34]. In this work some techniques that we have built to obtain 10-order symmetric composition methods of symmetric integrators of s = 31 stages (16 order conditions) are explored. Given some starting coefficients that satisfy the simplest five order conditions, the process followed to obtain the coefficients that satisfy the sixteen order conditions is provided.
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365 p.
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Se proyecta una rehabilitacion del mercado del Roquetas del Mar.