187 research outputs found

    REGIONAL AND URBAN SCIENCE IN FRANCE: RANKINGS OF AUTHORS AND INSTITUTIONS AND PUBLICATION PATTERNS DURING THE NINETIES

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    This article analyses the evolution experienced by research in urban and regional science in France between 1991 and 2000, comparing these changes with wider international trends. Nine of the leading international journals of regional and urban studies were used in drawing up rankings of countries, authors and institutions and in exploring publication patterns. We examine the strategy adopted by the French in establishing themselves within the world's top five in regional and urban research and report a number of interesting findings when comparisons are drawn internationally.REGIONAL AND URBAN SCIENCE, BIBLIOMETRICS, RANKINGS

    Smoothing the Catalan tourism micro-data time series

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    In this paper we propose a method for smoothing the Catalan tourism time series between 1997 and 2000. These time series, built upon a micro database drawn from a survey conducted by the Statistical Institute of Catalonia, are somewhat volatile due, it would seem, to the incomplete nature of the information. The application of a smoothing procedure based on the combination of classical techniques and weighted moving averages allows us to overcome the problems caused by this lack of information and to obtain time series that evolve smoothly over time

    Biodegradation and Mechanical Integrity of Magnesium and Magnesium Alloys Suitable for Implants

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    This book chapter deals with the fundamental aspects of corrosion of magnesium based alloys in bodily fluids and reviews the various techniques that can be used to tune their degradation rate. The time-dependent evolution of their mechanical properties during the biodegradation process is also outlined

    Regional economic dynamics and convergence in the european union

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    [eng] Deepening in the European Union (EU) integration process has enhanced the question of economic disparities at a regional level. The convergence process observed until the late seventies was exhausted onwards in coincidence with important changes in the economic activity. The paper showshow these factors would have provoked a regional differenciated response that,despite being important, would have not strengthened the decrease in regional inequalities. We use an alternative and (in our opinion) richer approach to the traditional convergence analysis, where the evolution of the whole regional distribution is what matters and not that of a representative economy. Moreover, when analysing inequalities among regional economies, the geographical space acquire an outstanding role. Hence, we apply spatial association tests and relate them to the convergence analysis[spa] El avance en el proceso de integración ha aumentado el interés por la evolución de las disparidades económicas entre las regiones de la Unión Europea. El proceso de convergencia observado hasta finales de los setenta parece haberse agotado, coincidiendo con importantes cambios en el desarrollo de la actividad económica. El trabajo muestra como estos factores habrían provocado una respuesta regional diferenciada que, pese a ser importante, no habría contribuido a la disminución de las disparidades. En el trabajo se utiliza una aproximación alternativa a la empleada en el tradicional análisis de convergencia, donde lo que se considera es la evolución de la totalidad de la distribución y no unicamente aquélla de una economía representativa. Adicionalmente, cuando se estudian las disparidades entre economías regionales, el espacio adquiere un papel destacado. Por ello se aplican contrastes de asociación espacial y se relacionan con el análisis de convergenci

    Crustal deformation in eastern Betics from CuaTeNeo GPS network

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    The eastern Betic Cordillera, Spain, is the most seismically active area within the Iberian Peninsula. We present a Global Positioning System (GPS)-derived horizontal crustal deformation obtained from five occupations of the CuaTeNeo GPS network (1997, 2002, 2006, 2009 and 2011) that clearly shows continuing tectonic activity in the SE Betics. The most prominent feature of the GPS velocity field is the NW oriented motion of the majority of the stations at rates ranging from 2 mm/yr near the coast to 0.5 mm/yr inland. This type of deformation indicates that the main driving force responsible for the observed velocities is related to the on-going convergence between Nubia and Eurasia plates. The calculated deformation field shows evidence for localized deformation related to active faults within the area. Most of the deformation is concentrated on the Alhama de Murcia fault, the source of the 2011 Lorca earthquake (Mw 5.2). We estimate a reverse-sinistral geodetic slip rate of 1.5 ± 0.3 mm/yr for this fault. Our crustal deformation field and analyses are important contributions to estimating seismic hazard for the eastern Betics, since it is the first time crustal deformation rates at this scale are presented

    Regional research in Spain:Countries ,institutions and authors rankings in regional and urban science for 1991-2000

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    This article analyzes which has been the evolution of the research in urban and regional science in Spain in the period 1991-2000 situating it in the international context.With this aim,we elaborate rankings of countries,authors and institutions in function of the publications carried out in a sample of nine top regional and urban international journals.The results show that the improvement in the international position of Spanish economic research found by other authors is also observed at the regional and urban level.In fact,this increase is motivated both by an increase of the publication of recognised authors and by the contribution of «new » authors

    Present-day deformation of the Pyrenees revealed by GPS surveying and earthquake focal mechanisms until 2011

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    The Pyrenean mountain range is a slowly deforming belt with continuous and moderate seismic activity. To quantify its deformation field, we present the velocity field estimated from a GPS survey of the Pyrenees spanning 18 yr. The PotSis and ResPyr networks, including a total of 85 GPS sites, were installed and first measured in 1992 and 1995 1997, respectively, and remeasured in 2008 and 2010. We obtain a deformation field with velocities less than 1 mm yr−1 across the range. The estimated velocities for individual stations do not differ significantly from zero with 95 per cent confidence. Even so, we estimate a maximum extensional horizontal strain rate of 2.0 ± 1.7 nanostrain per year in a N S direction in the western part of the range. We do not interpret the vertical displacements due to their large uncertainties. In order to compare the horizontal strain rates with the seismic activity, we analyse a set of 194 focal mechanisms using three methods: (i) the 'r' factor relating their P and T axes, (ii) the stress tensors obtained by fault slip inversion and (iii) the strain-rate tensors. Stress and strain-rate tensors are estimated for: (i) the whole data set, (ii) the eastern and western parts of the range separately, and (iii) eight zones, which are defined based on the seismicity and the tectonic patterns of the Pyrenees. Each of these analyses reveals a lateral variation of the deformation style from compression and extension in the east to extension and strike-slip in the west of the range. Although the horizontal components of the strain-rate tensors estimated from the seismic data are slightly smaller in magnitude than those computed from the GPS velocity field, they are consistent within the 2σ uncertainties. Furthermore, the orientations of their principal axes agree with the mapped active faults

    Using exchange bias to extend the temperature range of square loop behavior in [Pt/Co] multilayers with perpendicular anisotropy

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    This article may be downloaded for personal use only. Any other use requires prior permission of the author and the American Institute of Physics.The temperature dependence of the magnetic properties of [Pt/Co]multilayers (ML), exhibiting perpendicular anisotropy, with and without exchange biasing with an antiferromagnet(AFM) has been investigated. Upon heating, a loss of the out-of-plane anisotropy and, consequently, of the remanence to saturation ratio is observed in these systems. However, such effect occurs at higher temperatures in the [Pt/Co] ML exchange coupled to the AFM than for the unbiased ML. This is attributed to the additional anisotropy induced to the ML by the ferromagnetic-antiferromagnetic exchange coupling

    High-coercivity ultralight transparent magnets

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    This article may be downloaded for personal use only. Any other use requires prior permission of the author and the American Institute of Physics.Magnetic silica-aerogel composites have been synthesized by dispersing hard magnetic Nd2Fe14B particles in a sol during a fast sol-gel process and subsequently supercritically drying the resulting gels. The composites are found to retain most of the outstanding properties of their constituents: the large coercivity and moderate remanence of the magnetic powders and the transparency and low density of silica aerogels. Moreover, aerogels synthesized in the presence of a magnetic field exhibit the alignment of the particles, forming needle-like structures along the direction of the applied magnetic field, which results in optical and magnetic anisotropies. Due to their unique combination of properties, these types of materials may be appealing for magneto-optics and magnetic actuator applications
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