219 research outputs found

    Software para la corrección de las posibles imperfecciones existentes en los sensores de imagen

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    En este trabajo se indica la técnica utilizada para conseguir una buena corrección de las posibles deficiencias presentadas por los dispositivos de adquisición de imágenes. Se presenta la herramienta informática que ha sido desarrollada para este fin y que permite localizar la mejor corrección posible. También se puede evaluar, tanto objetiva como subjetivamente, la mejora conseguida con la corrección

    A Generalized Window Approach for Designing Transmultiplexers

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    This paper proposes a computational, very efficient, approach for designing a novel family of M-channel maximally decimated nearly perfect-reconstruction cosine-modulated transmultiplexers. This approach is referred to as the generalized windowing method for transmultiplexers because after knowing the transmission channel a proper weighted sum of the inter-channel and inter-symbol interferences can be properly taken into account in the optimization of the window function, unlike in other existing windowing techniques. The proposed approach has also the following two advantages. First, independent of the number of subchannels and the common order of the subchannel filters, the number of unknowns is only four. Second, the overall optimization procedure is made considerably fast by estimating the above-mentioned sum in terms of two novel measures, namely, the signal to inter-symbol and the signal to inter-channel interferences, which are very easy to evaluate. Furthermore, when the transmission channel is not considered in the design, a table is provided, which contains the parameters for designing the prototype filter directly by using the windowing method without any time-consuming optimization. When comparing the resulting transmultiplexers with the corresponding perfect-reconstruction designs (the same number of subchannels and same prototype filter order), the levels of interferences are practically the same. However, when the system is affected by a strong narrowband interference, the proposed transmultiplexers outperform their PR counterparts. Design examples are included illustrating the efficiency of the proposed design approach over other existing techniques based on the use of the windowing method

    El Proyecto SAF de Nowcasting (NWCSAF)

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    Estudio de repetibilidad y variación circadiana del índice de alternancias de la onda T del electrocardiograma en registros ambulatorios

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    Las alternancias en la Onda T en el electrocardiograma (ECG) miden la inestabilidad del corazón y son un indicador de posible riesgo a arritmias malignas. Se propone un estudio de la repetibilidad en las alternancias en registros Holters de 24 horas teniendo en cuenta el ritmo circadiano. Se comprobará la repetibilidad de la medida en distintos registros de los mismos pacientes, y se estudiará la variación intradía de este índice, y si pueden ser más predictivas o no del riesgo en función de la hora en que se midan.<br /

    Bimodal effect of water on V2O5/TiO2 catalysts with different vanadium species in the simultaneous NO reduction and 1,2-dichlorobenzene oxidation

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    VOX/TiO2 catalysts with different vanadium loading were prepared in order to study the influence of vanadium species on the effect of water in the simultaneous NO reduction through NH3-SCR and o-DCB oxidation reactions. The presence of isolated, polymeric and crystalline species and their redox and acid properties were evaluated by N2-Adsorption, XRD, Raman, H2-TPR, XPS and NH3-TPD. Water has a bimodal and reversible effect in both NO reduction and o-DCB oxidation depending on vanadium species and temperature. In SCR, water has a detrimental effect at low temperature due to competitive adsorption with NO and NH3, while at high temperature it promotes an increase of NO conversion associated to the suppression of side-reactions, which increase the selectivity towards N2. In o-DCB oxidation, the effect of water is the sum of two contributions: one positive, related to the removal of surface adsorbed detrimental species; and one negative, associated to the competitive adsorption with o-DCB. Thus, at high temperature water acts as inhibitor, while at low temperature water has a promotional effect in the highly dispersed vanadium catalysts due to their tendency to suffer deactivation, mainly by carbonaceous materials. The presence of water also favors total oxidation and decreases the formation of chlorinated by products.MINECO/FEDER (CTQ2015-64616-P), MINECO/FEDER (BES-2016-077849), IT657-13, IT1297- 19, INF12/37, UFI 11/39, PID2019-107503RB-I00, MCIN/AEI/10.13039/50110001103

    Stationary severe thunderstorms over Malaga on 19 February 2017

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    Póster presentado en: "Workshop on Using ECMWF’s Forecasts (UEF2017)", que se celebró en Reading, Reino Unido, del 12 al 16 de junio de 2017.During the dawn of 19 February 2017, a set of intense thunderstorms occurred over south Spain. Malaga city was especially affected by these thunderstorms. Precipitation, that started at about 01:30 UTC (02:30 local time) and lasted around 8 hours, peaked just after 02:00 UTC. The horizontal distribution of precipitation was quite variable, showing some maxima over the center and eastern Malaga city. This case study, that discusses the highly localized and stationary thunderstorms previously described, is tackled from both scales, synoptic and mesoscale, adding some issues at microscale. To carry out this task, deterministic outputs and convective diagnostic products of the ECMWF model, and remote sensing (radar, lightning and both basic and NWCSAF satellite products) and observation data products are used

    Dicyclopentadienyl zirconium and hafnium complexes with the bridged (dimethylsilanodiyl)dicyclopentadienyl [(SiMe2)(η5-C5H4)2]2 ligand. X-ray molecular structure of [Zr{(SiMe2)(η5-C5H4)2}(CH2Ph)]2(μ-O)

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    Reaction of the bridged (dimethylsilanediyl)dicyclopentadienyl dilithium salt [(SiMe2)(C5H4)2Li2] with MCl4, in toluene, gave the zirconium and hafnium complexes [M{(SiMe2)(η5-C5H4)2}Cl2] [M=Zr (1), Hf (2)]. Addition of two equivalents of M′R (M′=MgCl, R=CH3; M′=Li, R=CH2CMe2Ph; M′=MgBz, R=CH2Ph) to toluene or diethyl ether solutions of [M{(SiMe2)(η5-C5H4)2}Cl2] afforded the dialkyl derivatives [M{(SiMe2)(η5-C5H4)2}R2] [R=CH3, M=Zr (3), Hf (4); R=CH2CMe2Ph, M=Zr (5), Hf (6); R=CH2Ph, M=Zr (7)]. Compound 1 reacted with LiMe and Mg(CH2Ph)2(THF)2 in the presence of a stoichiometric amount of water to give the μ-oxo derivatives [Zr{(SiMe2)(η5-C5H4)2}R]2(μ-O) [R=CH3 (8), CH2Ph (9)]. The X-ray molecular structure of [Zr{(SiMe2)(η5-C5H4)2}(CH2Ph)]2(μ-O) (9) has been determined by diffraction methods. Its most remarkable feature is the planarity of the BzZrOZrBz and the linearity of the ZrOZr systems.We acknowledge the Dirección General de Investigación Científica y Técnica (Spain) for financial support of this research (Project PB97-0776)

    Desde la capacitación a la articulación. La experiencia de Construcciones 1 en extensión

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    The experience reported in this work is the product of a process developed for several years with different actors and institutions and enriched thanks to the experiences and needs that arose during the process. The activities began in 2009 as training for workers in municipalities in the interior of the Chaco. This initial project was adjusting and growing in commitment through the extension program "The University in the Middle" and the link with other institutions: Faculty of Engineering of the U.N.NE. and the U.E.P. UOCRA N ° 149. Thus we managed, in the successive years of implementation, to articulate the training of workers with the training of the faculty student, promoting the exchange of knowledge and work, bringing our students closer to professional practice in a process continuous feedback.La experiencia relatada en este trabajo es el producto de un proceso desarrollado desde hace varios años con diferentes actores e instituciones y enriquecido gracias a las experiencias y las necesidades que surgieron durante el proceso. Las actividades se iniciaron en 2009 como capacitaciones a obreros en municipios del interior del Chaco. Ese proyecto inicial fue ajustándose y creciendo en compromiso a través del programa de extensión “La Universidad en el Medio” y la vinculación con otras instituciones: Facultad de Ingeniería de la U.N.NE. y la U.E.P. N°149 de U.O.C.R.A.. Así logramos, en los años sucesivos de implementación, articular la capacitación de los obreros con la formación del alumno de la facultad, promoviendo el intercambio de conocimientos y trabajo, acercando a nuestros estudiantes a la práctica profesional en un proceso continuo de retroalimentación

    Emergency department direct discharge compared to short-stay unit admission for selected patients with acute heart failure: analysis of short-term outcomes

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    Insuficiència cardíaca; Serveis d'urgències mèdiques; MortalitatHeart failure; Emergency service, hospital; MortalityInsuficiencia cardíaca; Servicio hospitalario de urgencias; MortalidadShort stay unit (SSU) is an alternative to conventional hospitalization in patients with acute heart failure (AHF), but the prognosis is not known compared to direct discharge from the emergency department (ED). To determine whether direct discharge from the ED of patients diagnosed with AHF is associated with early adverse outcomes versus hospitalization in SSU. Endpoints, defined as 30-day all-cause mortality or post-discharge adverse events, were evaluated in patients diagnosed with AHF in 17 Spanish EDs with an SSU, and compared by ED discharge vs. SSU hospitalization. Endpoint risk was adjusted for baseline and AHF episode characteristics and in patients matched by propensity score (PS) for SSU hospitalization. Overall, 2358 patients were discharged home and 2003 were hospitalized in SSUs. Discharged patients were younger, more frequently men, with fewer comorbidities, had better baseline status, less infection, rapid atrial fibrillation and hypertensive emergency as the AHF trigger, and had a lower severity of AHF episode. While their 30-day mortality rate was lower than in patients hospitalized in SSU (4.4% vs. 8.1%, p < 0.001), 30-day post-discharge adverse events were similar (27.2% vs. 28.4%, p = 0.599). After adjustment, there were no differences in the 30-day risk of mortality of discharged patients (adjusted HR 0.846, 95% CI 0.637-1.107) or adverse events (1.035, 0.914-1.173). In 337 pairs of PS-matched patients, there were no differences in mortality or risk of adverse event between patients directly discharged or admitted to an SSU (0.753, 0.409-1.397; and 0.858, 0.645-1.142; respectively). Direct ED discharge of patients diagnosed with AHF provides similar outcomes compared to patients with similar characteristics and hospitalized in a SSU.Open Access funding provided thanks to the CRUE-CSIC agreement with Springer Nature. The author(s) disclosed receipt of the following fnancial support for the research, authorship, and/or publication of this article: This study was partially supported by grants from the Instituto de Salud Carlos III supported with funds from the Spanish Ministry of Health and FEDER (PI15/01019, PI18/00393) and Fundació La Marató de TV3 (2015/2510). The Emergencies: Processes and Pathologies research group of the IDIBAPS receives fnancial support from the Catalonian government for consolidated groups of investigation (GRC 2009/1385 and 2014/0313)

    Is a neutral expression also a neutral stimulus?: a study with functional magnetic resonance

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    Although neutral faces do not initially convey an explicit emotional message, it has been found that individuals tend to assign them an affective content. Moreover, previous research has shown that affective judgments are mediated by the task they have to perform. Using functional magnetic resonance imaging in 21 healthy participants, we focus this study on the cerebral activity patterns triggered by neutral and emotional faces in two different tasks (social or gender judgments). Results obtained, using conjunction analyses, indicated that viewing both emotional and neutral faces evokes activity in several similar brain areas indicating a common neural substrate. Moreover, neutral faces specifically elicit activation of cerebellum, frontal and temporal areas, while emotional faces involve the cuneus, anterior cingulated gyrus, medial orbitofrontal cortex, posterior superior temporal gyrus, precentral/postcentral gyrus and insula. The task selected was also found to influence brain activity, in that the social task recruited frontal areas while the gender task involved the posterior cingulated, inferior parietal lobule and middle temporal gyrus to a greater extent. Specifically, in the social task viewing neutral faces was associated with longer reaction times and increased activity of left dorsolateral frontal cortex compared with viewing facial expressions of emotions. In contrast, in the same task emotional expressions distinctively activated the left amygdale. The results are discussed taking into consideration the fact that, like other facial expressions, neutral expressions are usually assigned some emotional significance. However, neutral faces evoke a greater activation of circuits probably involved in more elaborate cognitive processing.This research was supported by a grant from Ministerio de Ciencia y Tecnología, Spain (MICINN-PSI-2009-09067)
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