Results for Channel Error Profiles for DECT

This letter presents the main statistical characterization of the underlying error process obtained in the case of the Digital European Cordless Telecommunications (DECT) radio system. By simulation of the transmission link, error sequences are generated for different channel parameters. Relevant statistics are then computed for the purpose of efficient channel coding design and evaluation

Detectors could spot plagiarism in research proposals

Having all been involved in proposal evaluation, we believe the studies indicate that a text matching analysis of research proposals could reduce plagiarism in subsequent publications. For instance, when European Commission evaluators have met in the past to evaluate research proposals, they received printed copies which had to be returned before the panel members left, and had no computer access during deliberations. A plagiarism detector using text-mining methods could be used instead of the current security measures. Such a system could, in principle, detect similarities to previous submissions and uncited sources using advanced document segmentation. Only official agencies have access to confidential proposals and the funds to experiment with automated plagiarism-detectors. It is important that they should investigate these approaches to reducing the possibility of scientific misconduct

Experimental evaluation of Stress Intensity Factors from strain fields using Digital Image Correlation

P Lopez-Crespo, A. Garcia-Gonzalez, Experimental evaluation of Stress Intensity Factors from strain fields using Digital Image Correlation, Proceedings of Jornadas Idmati 2014, Barcelona, junio de 2014Optical techniques offer many benefits to experimentalist compared with gauge methods. Optical techniques such as holographic interferometry, electronic speckle pattern interferometry, photo- and thermoelasticity, and various grid methods are non-contact, full-field and can have high resolution. However, they are expensive or require special surface preparation or provide reliable measurements only in certain locations (fringes). Moreover, these techniques are hard to apply in field conditions. In contrast, the image correlation technique is cheap, easy, versatile and requires minimal surface preparation. It is ideally suited for field application. In this work a two-dimensional image correlation method was used to measure in-plane displacement fields near crack tip. Linear elasticity was assumed outside the crack tip plasticity zone. In the elastic region Muskhelishvili's complex functions approach was used to calculate the stress intensity factors from the measured displacements. functions were used to calculate the stress intensity factors from the measured displacements. Computationally the problem is that of solving an overdetermined system of non-linear equations. In this work genetic algorithm was used to find the solution. The method was applied to fatigue cracks in 2 and 3 mm thick Al 7010 alloy plates loaded under mixed mode (I+II). The stress intensity factors were calculated to within 10-20% of the nominal applied values. In addition the crack tip location was calculated. The sensitivity of the technique to the experimental noise and the issues of the location and the number of the experimental data points will be discussed. Finally the extention of the method to a real time monitoring will be analysed.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech

Uso del vídeo para el fact-checking en Facebook. Análisis de la evolución y el alcance de la producción iberoamericana (2016-2021)

Social networks –and Facebook in particular– have become an important element of the information diet for millions of people around the world. By using them, the traditional media lose control of the distribution channel for their content, whose reach now depends, firstly, on the relevance criteria established by the networks themselves and, secondly, on the interactions generated by the audience with each publication. Very often research on journalism has tackled the issue of reach and how efficient fact-checkers are. To find answer to the sociodemographic features of their audiences or the characteristics of their posts are explored. However, factors such as the influence of the algorithms which choose the content users are shown on the social networks is not often dealt with. This article aims to contribute in both areas. Firstly, it offers a broad perspective on the publications of Ibero-American fact-checkers on Facebook between 2016 and 2021, focuses on the evolution of video production (n=9075) and on the views and engagement achieved by this format with respect to the rest, and relates them to changes in the News Feed algorithm. Secondly, it proposes a content analysis to identify formal and thematic elements in the most popular videos in the same period (n=414) and relates them to previous research. Our results show significant similarities in popular videos, but also changes in video production, a generalized decrease in the ratio of views and a drop in the interaction rate more accentuated than in all the publications of the period. Although the focus of this research does not allow us to make direct causal inferences, the trends identified coincide with the changes in the Facebook News Feed algorithm that were made public in those years.Las redes sociales –y Facebook en particular– se han convertido en un elemento importante de la dieta informativa para millones de personas en todo el mundo. Al utilizarlas, los medios de comunicación tradicionales pierden el control del canal de distribución de sus contenidos, cuyo alcance depende ahora, en primer lugar, de los criterios de relevancia establecidos por las propias redes y, en segundo lugar, de las interacciones generadas por la audiencia en cada publicación. La investigación sobre periodismo ha abordado en múltiples ocasiones el problema del alcance y la eficacia de los fact-checkers, buscando respuestas en los rasgos sociodemográficos de sus audiencias o en las características de sus publicaciones, sin embargo, suelen obviarse factores como la influencia de los algoritmos que seleccionan el contenido al que los usuarios se ven expuestos en las redes sociales. Este artículo trata de realizar una contribución en ambas vertientes: en primer lugar ofrece un análisis sobre la evolución de la producción, visionados y engagement de los vídeos publicados por los fact-checkers iberoamericanos en Facebook entre 2016 y 2021 (n=9.075), los compara con los datos del total de publicaciones y los relaciona con cambios en el algoritmo del News Feed; en segundo lugar plantea un análisis de contenido para identificar elementos formales y temáticos en los vídeos de mayor éxito en el mismo período (n=414) y los pone en relación con la investigación previa. Nuestros resultados permiten identificar características comunes a los vídeos de mayor éxito pero también cambios en la producción de vídeo, y caídas en los ratios de visualizaciones e interacciones más acentuadas que en el conjunto de publicaciones del periodo. Aunque el enfoque de esta investigación no permite hacer inferencias causales directas, las tendencias identificadas coinciden con modificaciones en el algoritmo del News Feed de Facebook con respecto al vídeo

Influence of Ultraviolet Radiation Exposure Time on Styrene-Ethylene-Butadiene-Styrene (SEBS) Copolymer

[EN] The effect of ultraviolet radiation on styrene-ethylene-butadiene-styrene (SEBS) has been studied at different exposures times in order to obtain a better understanding of the mechanism of ageing. The polymer materials were mechanically tested and then their surfaces were analyzed using a scanning electron microscope (SEM) and atomic force microscopy (AFM). Moreover, the optical analysis of contact angle (OCA) was used to evaluate the surface energy (gamma(s)) and the yellowing index (YI) and attenuated total reflectance infrared spectroscopy (ATR-FTIR) were used to observe structural and physical changes in aging SEBS. The results obtained for the SEBS, in relation to the duration of exposure, showed superficial changes that cause a decrease in the surface energy (gamma(s)) and, therefore, a decrease in surface roughness. This led to a reduction in mechanical performance, decreasing the tensile strength by about 50% for exposure times of around 200 hours.This work was supported by the Ministry of Economy and Competitiveness (MINECO) grant number MAT2017-84909-C2-2-R). Daniel Garcia-Garcia acknowledges Generalitat Valenciana (GVA) for financial support through a postdoctoral contract (APOSTD/2019/201).Garcia-Garcia, D.; Crespo, J.; Parres, F.; Samper, M. (2020). Influence of Ultraviolet Radiation Exposure Time on Styrene-Ethylene-Butadiene-Styrene (SEBS) Copolymer. Polymers. 12(4):1-14. https://doi.org/10.3390/polym12040862S114124Picchioni, F., Giorgi, I., Passaglia, E., Ruggeri, G., & Aglietto, M. (2001). Blending of styrene-block-butadiene-block-styrene copolymer with sulfonated vinyl aromatic polymers. Polymer International, 50(6), 714-721. doi:10.1002/pi.692Zhu, J., Birgisson, B., & Kringos, N. (2014). Polymer modification of bitumen: Advances and challenges. 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Polymer Degradation and Stability, 96(6), 1104-1110. doi:10.1016/j.polymdegradstab.2011.03.003Allen, N. (2004). Photooxidation of styrene–ethylene–butadiene–styrene (SEBS) block copolymer. Journal of Photochemistry and Photobiology A: Chemistry, 162(1), 41-51. doi:10.1016/s1010-6030(03)00311-3Flaris, V., & Stachurski, Z. H. (1992). The effects of processing on the mechanical properties of a polyolefin blend. Polymer International, 27(3), 267-273. doi:10.1002/pi.4990270312Li, Y., Li, L., Zhang, Y., Zhao, S., Xie, L., & Yao, S. (2009). Improving the aging resistance of styrene-butadiene-styrene tri-block copolymer and application in polymer-modified asphalt. Journal of Applied Polymer Science, n/a-n/a. doi:10.1002/app.31458Xu, X., Yu, J., Xue, L., Zhang, C., He, B., & Wu, M. (2017). Structure and performance evaluation on aged SBS modified bitumen with bi- or tri-epoxy reactive rejuvenating system. Construction and Building Materials, 151, 479-486. doi:10.1016/j.conbuildmat.2017.06.102Si Bachir, D., Dekhli, S., & Ait Mokhtar, K. (2016). Rheological Evaluation of Ageing Properties of SEBS Polymer Modified Bitumens. Periodica Polytechnica Civil Engineering, 397-404. doi:10.3311/ppci.7853Awaja, F., Gilbert, M., Kelly, G., Fox, B., & Pigram, P. J. (2009). Adhesion of polymers. Progress in Polymer Science, 34(9), 948-968. doi:10.1016/j.progpolymsci.2009.04.007Poisson, C., Hervais, V., Lacrampe, M. F., & Krawczak, P. (2006). Optimization of PE/binder/PA extrusion blow-molded films. II. Adhesion properties improvement using binder/EVA blends. Journal of Applied Polymer Science, 101(1), 118-127. doi:10.1002/app.22407Zhang, H., Guo, W., Yu, Y., Li, B., & Wu, C. (2007). Structure and properties of compatibilized recycled poly(ethylene terephthalate)/linear low density polyethylene blends. 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Colloids and Surfaces A: Physicochemical and Engineering Aspects, 156(1-3), 85-93. doi:10.1016/s0927-7757(99)00061-8Zhang, X., Xie, F., Pen, Z., Zhang, Y., Zhang, Y., & Zhou, W. (2002). Effect of nucleating agent on the structure and properties of polypropylene/poly(ethylene–octene) blends. European Polymer Journal, 38(1), 1-6. doi:10.1016/s0014-3057(01)00182-3Beholz, L. G., Aronson, C. L., & Zand, A. (2005). Adhesion modification of polyolefin surfaces with sodium hypochlorite in acidic media. Polymer, 46(13), 4604-4613. doi:10.1016/j.polymer.2005.03.086Kinloch, A. J. (1980). The science of adhesion. Journal of Materials Science, 15(9), 2141-2166. doi:10.1007/bf00552302Lippert, T., & Dickinson, J. T. (2003). Chemical and Spectroscopic Aspects of Polymer Ablation:  Special Features and Novel Directions. Chemical Reviews, 103(2), 453-486. doi:10.1021/cr010460qVan der Leeden, M. C., & Frens, G. (2002). Surface Properties of Plastic Materials in Relation to Their Adhering Performance. 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Comparative study on the surface free energy of a solid calculated by different methods. Polymer Testing, 26(1), 14-19. doi:10.1016/j.polymertesting.2006.08.005Kumar, S., & Misra, R. K. (2007). Analysis of Banana Fibers Reinforced Low‐density Polyethylene/Poly(Є‐caprolactone) Composites. Soft Materials, 4(1), 1-13. doi:10.1080/15394450600823040Fowkes, F. ., McCarthy, D. ., & Mostafa, M. . (1980). Contact angles and the equilibrium spreading pressures of liquids on hydrophobic solids. Journal of Colloid and Interface Science, 78(1), 200-206. doi:10.1016/0021-9797(80)90508-1Owens, D. K., & Wendt, R. C. (1969). Estimation of the surface free energy of polymers. Journal of Applied Polymer Science, 13(8), 1741-1747. doi:10.1002/app.1969.070130815Zhao, Y., Tang, S., Myung, S.-W., Lu, N., & Choi, H.-S. (2006). Effect of washing on surface free energy of polystyrene plate treated by RF atmospheric pressure plasma. 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Educación y satisfacción con la vida: un análisis con la World Values Survey

En este trabajo se adopta un enfoque de satisfacción con la vida para analizar si la educación contribuye al bienestar de los individuos, más allá del impacto positivo que ésta puede tener a través de variables como los ingresos o el estado subjetivo de salud. Para ello, se han utilizado los microdatos procedentes de la World Values Survey para dos grupos de países relativos al período 2010-2014. En particular, los individuos seleccionados para el análisis pertenecen a siete países de la OCDE y a los que integran el grupo BRICS. El análisis consiste en modelizar, mediante modelos probit ordenados, la probabilidad de que el individuo se encuentre en un determinado nivel de satisfacción con la vida en función de su educación, una vez controlada la heterogeneidad individual observada. Además, se incluyen efectos fijos por países en cada uno de los dos grupos considerados. Los resultados indican un efecto positivo de la educación sobre el bienestar, una vez descontado el impacto de la renta y la salud sobre aquél, efecto que se mantiene para el estrato de renta media cuando se segmenta la muestra por niveles de ingresos, poniendo de manifiesto el componente de consumo de la educación.Universidad de Málaga. Campus de Excelencia de Andalucía Tech

Selection of ovine housekeeping genes for normalisation by real-time RT-PCR; analysis of PrP gene expression and genetic susceptibility to scrapie

BACKGROUND: Cellular prion protein expression is essential for the development of transmissible spongiform encephalopathies (TSEs), and in sheep, genetic susceptibility to scrapie has been associated to PrP gene polymorphisms. To test the hypothetical linkage between PrP gene expression and genetic susceptibility, PrP mRNA levels were measured by real-time RT-PCR in six ovine tissues of animals with different genotypes. RESULTS: Previous to the PrP gene expression analysis the stability of several housekeeping (HK) genes was assessed in order to select the best ones for relative quantification. The normalisation of gene expression was carried out using a minimum of three HK genes in order to detect small expression differences more accurately than using a single control gene. The expression stability analysis of six HK genes showed a large tissue-associated variation reflecting the existence of tissue-specific factors. Thereby, a specific set of HK genes was required for an accurate normalisation of the PrP gene expression within each tissue. Statistical differences in the normalised PrP mRNA levels were found among the tissues, obtaining the highest expression level in obex, followed by ileum, lymph node, spleen, cerebellum and cerebrum. A tendency towards increased PrP mRNA levels and genetic susceptibility was observed in central nervous system. However, the results did not support the hypothesis that PrP mRNA levels vary between genotypes. CONCLUSION: The results on PrP gene expression presented here provide valuable baseline data for future studies on scrapie pathogenesis. On the other hand, the results on stability data of several HK genes reported in this study could prove very useful in other gene expression studies carried out in these relevant ovine tissues

A Hardware Architecture for Scheduling Complex Real-Time Task Sets

The problem of jointly scheduling both hard deadline periodic tasks and soft aperiodic tasks has been the subject of considerable research in real-time systems. One of the most widely accepted solutions for this problem are slack stealing algorithms. However, these algorithms are rather impractical, since they all imply a considerable scheduler overhead. This paper faces the overhead problem by introducing a complete hardware architecture that implements slack stealing in hardware using an optimal algorithm redesigned to be implemented efficiently in hardware. The proposed solution is a circuit that behaves as a kind of sophisticated interrupt controller taking the task workload and the interrupts as inputs, and providing the highest priority task to be executed in the CPU. From the point of view of hardware design, the algorithm involves two main problems: first, to select the highest priority task at every moment and, second, to locate a set of slack gaps in a real-time computation. Locating slack gaps in a real-time computation is a problem that requires to “look forward in time” into the forecast schedule of a given workload. This paper analyses the different approaches for solving this problem and presents a novel architecture to solve it efficiently using a technique based on an event-driven simulation of the future of a real-time computation. A timing analysis of the proposed design is also presented

Origin of orbital ferromagnetism and giant magnetic anisotropy at the nanoscale

The origin of orbital magnetism recently observed in different nanostructured films and particles is discussed as a consequence of spin-orbit coupling. It is shown that contact potentials induced at the thin film surface by broken symmetries, as domain boundaries in self-assembled monolayers, lead to orbital states that in some cases are of large radius. The component of the angular momentum normal to the surface can reach very high values that decrease the total energy by decreasing spin-orbit interaction energy. Intraorbital ferromagnetic spin correlations induce orbital momenta alignment. The estimated values of the magnetic moments per atom are in good agreement with the experimental observations in thiol capped gold films and nanoparticles