933 research outputs found

    La clasificación hotelera en la Unión Europea: un mercado poco común

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    ¿Son las estrellas símbolo de calidad en los establecimientos hoteleros? ¿Son las mismas estrellas, las que iluminan toda Europa? Estas son preguntas que se hacen muchas personas en el momento de seleccionar su alojamiento turístico. A día de hoy, pocas han sido las iniciativas europeas armonizadoras de los sistemas de clasificación hoteleros aplicables en los distintos países miembros. Tal hecho, conlleva la coexistencia en Europa de normativas voluntarias y obligatorias, clasificaciones con categorías que no se corresponden a las tradicionales estrellas y criterios que varían mucho de un país a otro. Un panorama dispar, que bien seguro condicionará el futuro de muchas empresas y algunos destinos turísticos.Are the stars symbol of quality in hotels? Are the same stars, those which illuminate Europe? These are questions that many people ask themselves, when they have to select their accommodation. Nowadays, there have been a few number of initiatives, having as objective the harmonization of the classification systems existing in the European Union. This fact implies the coexistence in Europe of compulsory and voluntary laws, classifications that do not correspond with the traditional star-system, and criterions that vary from one country to other. This creates an uneven panorama, which will certainly influence the future of many enterprises and some touristic destinations

    Enabling data analytics and machine learning for 5G services within disaggregated multi-layer transport networks

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    Recent advances, related to the concepts of Artificial Intelligence (AI) and Machine Learning (ML) and with applications across multiple technology domains, have gathered significant attention due, in particular, to the overall performance improvement of such automated systems when compared to methods relying on human operation. Consequently, using AI/ML for managing, operating and optimizing transport networks is increasingly seen as a potential opportunity targeting, notably, large and complex environments.Such AI-assisted automated network operation is expected to facilitate innovation in multiple aspects related to the control and management of future optical networks and is a promising milestone in the evolution towards autonomous networks, where networks self-adjust parameters such as transceiver configuration.To accomplish this goal, current network control, management and orchestration systems need to enable the application of AI/ML techniques. It is arguable that Software-Defined Networking (SDN) principles, favouring centralized control deployments, featured application programming interfaces and the development of a related application ecosystem are well positioned to facilitate the progressive introduction of such techniques, starting, notably, in allowing efficient and massive monitoring and data collection.In this paper, we present the control, orchestration and management architecture designed to allow the automatic deployment of 5G services (such as ETSI NFV network services) across metropolitan networks, conceived to interface 5G access networks with elastic core optical networks at multi Tb/s. This network segment, referred to as Metro-haul, is composed of infrastructure nodes that encompass networking, storage and processing resources, which are in turn interconnected by open and disaggregated optical networks. In particular, we detail subsystems like the Monitoring and Data Analytics or the in-operation planning backend that extend current SDN based network control to account for new use cases.Peer ReviewedPostprint (author's final draft

    The Federated Practice of Soccer Influences Hamstring Flexibility in Healthy Adolescents: Role of Age and Weight Status

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    The aim of this study was to compare the hamstring flexibility between federated soccer and non-federated adolescents, and also to evaluate the effect of age and weight status on hamstring flexibility. The participants were 234 students (11-18 years old) divided into: (i) G1: non-federated (n = 127), and (ii) G2: federated in soccer (n = 107). The deep flexion of the trunk (DF) test and the sit and reach test (SRT) were performed. G2 showed higher values for the DF and SRT compared to G1 (p < 0.05). Both flexibility tests correlated positively (r = 0.4, p < 0.001). Body mass index (BMI) was negatively correlated with the DF test (r = -0.3, p < 0.001), but not with the SRT. Divided by BMI, the underweight and normal weight groups had higher scores in the DF test compared with the overweight and obese groups (p < 0.001). BMI was negatively correlated with hamstring flexibility. Federated soccer students present higher scores of hamstring flexibility

    Estudio comparativo entre pacientes perfundidos con oxigenadores de membrana de fibra hueca y el oxigenador de burbujas D-700E

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    Different models of membrane oxygenators (MO group) and of D-700E bubble oxygenators (BO group) were comparatively studied in 24 patients with extracorporeal circulation valve surgery on the basis of several evolving variables such as: lenght of ischemic heart arrest, conciousness recovery time, intubation time, lenght of stay at surgical ICU, diuresis, postoperative bleeding, arrhythmias and postoperative complications, and surgery economic cest for each group. The study revealed a significant increase (p > 0.05) of lenght of stay at hospital in the BO group (14 ± 7 days) whereas this parameter was lower in MO group (8 ± 3 days). Arrhytmias were observed in 69 % of perfused patients with BO at the starting of reperfusion but this figure dropped to 38 % in patients treated with MO. Unit cost per BO patient was 1 124.48 and bed day cost was 1 145.24 whereas unit cost per MO patient was 642.56 and bed day cost 97.28. These results showed the economic and recovery advantages reported in the use of membrane oxygenators.Se realizó un estudio comparativo entre diferentes modelos de oxigenadores de membrana de fibra hueca (grupo OM) y el oxigenador de burbujas D-700E (grupo OB), en 24 pacientes sometidos a cirugía valvular con circulación extracorpórea, respecto a diferentes variables evolutivas, tales como: tiempo de paro isquémico, tiempo de recuperación de la conciencia, tiempo de extubación, tiempo de estadía en la unidad de cuidados intensivos quirúrgicos, diuresis, sangrado posoperatorio, arritmias y complicaciones posoperatorias; además se analizó el costo económico de la operación en cada grupo de pacientes. El estudio reportó un incremento significativo (p < 0,05) del tiempo de estadía en la sala de 14 ± 7 días en el grupo OB, el cual se redujo a 8 ± 3 días en el grupo OM. El desarrollo de arritmias al inicio de la reperfusión se observó en el 69 % de los pacientes perfundidos con OB, disminuyendo al 38 % en los casos tratados con OM. En el grupo OB el costo unitario por paciente fue de 1,124.48yelcostodıˊascamade1,124.48 y el costo días cama de 1,045.24, mientras que en el grupo OM el costo unitario por paciente fue de 642.56yde 642.56 y de 597.28 el costo días cama, reflejando con estos resultados las ventajas económicas y evolutivas que reportó utilizar los oxigenadores de membrana

    A control and management architecture supporting autonomic NFV services

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    The proposed control, orchestration and management (COM) architecture is presented from a high-level point of view; it enables the dynamic provisioning of services such as network data connectivity or generic network slicing instances based on virtual network functions (VNF). The COM is based on Software Defined Networking (SDN) principles and is hierarchical, with a dedicated controller per technology domain. Along with the SDN control plane for the provisioning of connectivity, an ETSI NFV management and orchestration system is responsible for the instantiation of Network Services, understood in this context as interconnected VNFs. A key, novel component of the COM architecture is the monitoring and data analytics (MDA) system, able to collect monitoring data from the network, datacenters and applications which outputs can be used to proactively reconfigure resources thus adapting to future conditions, like load or degradations. To illustrate the COM architecture, a use case of a Content Delivery Network service taking advantage of the MDA ability to collect and deliver monitoring data is experimentally demonstrated.Peer ReviewedPostprint (author's final draft

    Resumen de la tarea Rest-Mex en IberLEF 2023: Investigaci´on sobre An´alisis de Sentimiento para Textos Tur´ısticos Mexicanos

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    This paper presents the framework and results of the Rest-Mex task at IberLEF 2023, focusing on sentiment analysis and text clustering of tourist texts. The study primarily focuses on texts related to tourist destinations in Mexico, although this edition included data from Cuba and Colombia for the first time. The sentiment analysis task aims to predict the polarity of opinions expressed by tourists, classifying the type of place visited, whether it’s a tourist attraction, hotel, or restaurant, as well as the country it is located in. On the other hand, the text clustering task aims to classify news articles related to tourism in Mexico. For both tasks, corpora were built using Spanish opinions extracted from TripAdvisor and news articles from Mexican media. This article compares and discusses the results obtained by the participants in both sub-tasks. Additionally, a method is proposed to measure the easiness of a multi-class text classification corpus, along with an approach for system selection in a possible late fusion scheme.Este artículo presenta el marco y los resultados de la tarea Rest-Mex en IberLEF 2023, que se enfoca en el análisis de sentimiento y agrupamiento de textos turísticos. El estudio se centra principalmente en textos relacionados con destinos turísticos en México, aunque esta edición incluyó datos de Cuba y Colombia por primera vez. La tarea de análisis de sentimiento tiene como objetivo predecir la polaridad de opiniones expresadas por turistas, clasificando el tipo de lugar visitado, ya sea un atractivo turístico, un hotel o un restaurante, así como el país en el que se encuentra. Por otro lado, la tarea de agrupamiento de textos busca clasificar noticias relacionadas con el turismo en México. Para ambas tareas, se construyeron corpus utilizando opiniones en español extraídas de TripAdvisor y noticias de medios mexicanos. En este artículo, se comparan y discuten los resultados obtenidos por los participantes en ambas sub tareas. Además, se propone un método para medir la facilidad de un corpus de clasificación textual multi-clase, así como un enfoque para la selección de sistemas en un posible esquema de fusión tardía.The authors thank the Mexican Academy of Tourism Research (AMIT) for their support of the project ”Creation of a labeled database related to tourist destinations for training artificial intelligence models for classifying relevant topics” through the call ”I Research Projects 2022”, which originated this work

    Iterative dual-metal and energy transfer catalysis enables stereodivergence in alkyne difunctionalization: Carboboration as case study

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    Stereochemically defined tetrasubstituted olefins are widespread structural elements of organic molecules and key intermediates in organic synthesis. However, flexible methods enabling stereodivergent access to E and Z isomers of fully substituted alkenes from a common precursor represent a significant challenge and are actively sought after in catalysis, especially those amenable to complex multifunctional molecules. Herein, we demonstrate that iterative dual-metal and energy transfer catalysis constitutes a unique platform for achieving stereodivergence in the difunctionalization of internal alkynes. The utility of this approach is showcased by the stereodivergent synthesis of both stereoisomers of tetrasubstituted β-boryl acrylates from internal alkynoates with excellent stereocontrol via sequential carboboration and photoisomerization. The reluctance of electron-deficient internal alkynes to undergo catalytic carboboration has been overcome through cooperative Cu/Pd-catalysis, whereas an Ir complex was identified as a versatile sensitizer that is able to photoisomerize the resulting sterically crowded alkenes. Mechanistic studies by means of quantum-chemical calculations, quenching experiments, and transient absorption spectroscopy have been applied to unveil the mechanism of both stepsPGC2018-098660−B-I00, Horizon2020 (ERC) No.648319, PID2019-106315RB-I00, PID2020-118593RB-C22

    Identification of the presence of ischaemic stroke lesions by means of texture analysis on brain magnetic resonance images

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    Study funding This work was funded by the Row Fogo Charitable Trust (MVH, VGC) grant no. BRO-D.FID3668413, and the Wellcome Trust (patient recruitment, scanning, primary study Ref No. 088134/Z/09). The study was conducted independently of the funders who do not hold the data and did not participate in the study design or analyses. The Lothian Birth Cohort 1936 is funded by Age UK (Disconnected Mind grant) and the Medical Research Council (MRC; MR/M01311/1, G1001245, 82800), and the latter supported BSA. IJD was supported by the Centre for Cognitive Ageing and Cognitive Epidemiology, which is funded by the MRC and the Biotechnology and Biological Sciences Research Council (MR/K026992/1). David Moratal acknowledges financial support from the Spanish Ministerio de Economía y Competitividad (MINECO) and FEDER funds under Grant BFU2015-64380-C2-2-R, and from the Conselleria d'Educació, Investigació, Cultura i Esport, Generalitat Valenciana (grants AEST/2017/013 and AEST/2018/021). Rafael Ortiz-Ramón was supported by grant ACIF/2015/078 and grant BEFPI/2017/004 from the Conselleria d’Educació, Investigació, Cultura i Esport of the Valencian Community (Spain).Peer reviewedPublisher PD

    Robust Resolution-Enhanced Prostate Segmentation in Magnetic Resonance and Ultrasound Images through Convolutional Neural Networks

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    [EN] Prostate segmentations are required for an ever-increasing number of medical applications, such as image-based lesion detection, fusion-guided biopsy and focal therapies. However, obtaining accurate segmentations is laborious, requires expertise and, even then, the inter-observer variability remains high. In this paper, a robust, accurate and generalizable model for Magnetic Resonance (MR) and three-dimensional (3D) Ultrasound (US) prostate image segmentation is proposed. It uses a densenet-resnet-based Convolutional Neural Network (CNN) combined with techniques such as deep supervision, checkpoint ensembling and Neural Resolution Enhancement. The MR prostate segmentation model was trained with five challenging and heterogeneous MR prostate datasets (and two US datasets), with segmentations from many different experts with varying segmentation criteria. The model achieves a consistently strong performance in all datasets independently (mean Dice Similarity Coefficient -DSC- above 0.91 for all datasets except for one), outperforming the inter-expert variability significantly in MR (mean DSC of 0.9099 vs. 0.8794). When evaluated on the publicly available Promise12 challenge dataset, it attains a similar performance to the best entries. In summary, the model has the potential of having a significant impact on current prostate procedures, undercutting, and even eliminating, the need of manual segmentations through improvements in terms of robustness, generalizability and output resolutionThis work has been partially supported by a doctoral grant of the Spanish Ministry of Innovation and Science, with reference FPU17/01993Pellicer-Valero, OJ.; González-Pérez, V.; Casanova Ramón-Borja, JL.; Martín García, I.; Barrios Benito, M.; Pelechano Gómez, P.; Rubio-Briones, J.... (2021). 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    Mathematical Modelling and Identification of a Quadrotor

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    Motivated by the important growth of VTOL vehicles research such as quadrotors and to a small extent autonomous flight, a quadrotor dynamical model is presented in this work. The purpose of this study is to get a better understanding of its flight dynamics. It is an underactuated system. So, a simplified and clear model is needed to implement controllers on these kind of unmanned aerial systems. In addition, a computational tool is used for validation purposes. For future works embedded or intelligent control systems can be developed to control them. Gyroscopic and some aerodynamics effects are neglected
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