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[EN] Adapting curricula to the European space for higher education has been an opportunity for Spanish universities to perform a new approach to the structure of their degrees. In this process takes a special importance incorporate new technologies to the university system, a task that had been initiated in an isolated way in the last years of XX century, but now became in a strategic action for universities. In institutions of higher education, there is a growing movement towards the use of e-Learning platforms to support access to educational or academic activities, also known as "Virtual Learning Environments, VLE" or "Learning Management Systems LMS, to support access to educational resources, the academic activities or the incorporation of new methodologies, however, without an assurance of quality, this effort and investment would not be productive. In this paper a method of assessing a virtual university experience is proposed, which allows the use of a quality model, incorporating a web tool to effectively manage both the design process, and the implementation and presentation of results. In addition, there are two case studies with different scopes and purposes, obtaining comparable results that support the efficiency of the proposed method., Este trabajo ha sido parcialmente financiado por el Ministerio de Educación y Ciencia, Spain, TIN2005-08788-C04-02 Proyecto AEEVA, y el Proyecto de excelencia GR47 de la Junta de Castilla y León. Spain.

We report on temperature sensors based on regenerated fiber Bragg gratings (RFBGs) for measurements up to 1100°C. The annealing process required to regenerate such gratings makes the optical fiber too delicate, thus making an adequate packaging necessary. Prior to the grating regeneration the optical fiber is protected with a ceramic tube which in turn is shielded with a thick metal casing. We have performed a thorough characterization of the thermo-optical response of both packaged and unpackaged RFBG sensors placing especial attention on possible residual hysteresis after several temperature cycling tests. The response and recovery times of packaged sensors were found to be, respectively, ~ 9 s and ~ 22 s. © 2006 IEEE., This work was supported in part by the Ministerio de Ciencia e Innovacion, Spain, through projects TEC2007-68065-C03-01, SO-PROMAC No. P41/08, in part by the "Ramon y Cajal" Program, and in part by the European COST Action 299 FIDES. This is an expanded paper from the 4th European Workshop on Optical Fiber Sensors, Porto, Portugal, September 8-10, 2010. Date of publication March 03, 2011; date of current version November 29, 2011. The associate editor coordinating the review of this manuscript and approving it for publication was Dr. William MacPherson.

Current broadcast digital networks make use of either a Single Frequency Network (SFN) or a Multi Frequency Network (MFN). None of these networks topologies is ideally suited for delivery of both global and local services in an efficiently way. MFNs enable the transmission of local services but need a significant amount of frequencies and therefore large amounts of valuable spectrum. SFNs are especially suitable for global services due to mutual support of the signals from multiples transmitters operated in the same frequency. SFNs are very spectrum efficiently; however they do not support local services. In this paper a hierarchical modulation method and Time Slicing technology are proposed for providing local and global contents in a terrestrial SFN (such DVB-T) keeping all its advantages. The hierarchical modulation has already been included in the DVB-T standard and time slicing solution is backwards compatible, in the sense that receivers that have been deployed in the original system can continue receiving data without hardware modifications. The performances of these technical solutions for both global and local services are analyzed. The applicability of these concepts is shown by a signal propagation simulation and coverage estimation in real scenario of Valencia region (Spain). © 2005 IEEE.