1,936 research outputs found

    Wireless Sensor Networks and Real-Time Locating Systems to Fight against Maritime Piracy

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    There is a wide range of military and civil applications where Wireless Sensor Networks (WSNs) and Multi-Agent Systems (MASs) can be used for providing context-awareness for troops and special corps. On the one hand, WSNs comprise an ideal technology to develop Real-Time Locating Systems (RTLSs) aimed at indoor environments, where existing global navigation satellite systems do not work properly. On the other hand, agent-based architectures allow building autonomous and robust systems that are capable of working on highly dynamic scenarios. This paper presents two piracy scenarios where the n-Core platform can be applied. n-Core is a hardware and software platform intended for developing and deploying easily and quickly a wide variety of WSNs applications based on the ZigBee standard. In the first scenario a RTLS is deployed to support boarding and rescue operations. In the second scenario a multi-agent system is proposed to detect the unloading of illegal traffic of merchandise at ports

    Advantages of using RTLS and WSN to enable efficient power consumption

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    The use of Real Time Locating Systems is gradually spreading in different areas of society. Multiple sectors, such as industry, security or healthcare are already taking advantage of the benefits of knowing the exact position of people, animals or objects. Energy consumption can also be improved by the use of RTLS and thanks to these systems we can model the habits of users both at home and in public buildings. This information will create consumption maps based on the use of different electronic devices or the use of different spaces. Thus, the election of the best energy tariff or when the best moment is to use appliances will be an easier process

    Distributional and classical solutions to the Cauchy Boltzmann problem for soft potentials with integrable angular cross section

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    This paper focuses on the study of existence and uniqueness of distributional and classical solutions to the Cauchy Boltzmann problem for the soft potential case assuming Sn1S^{n-1} integrability of the angular part of the collision kernel (Grad cut-off assumption). For this purpose we revisit the Kaniel--Shinbrot iteration technique to present an elementary proof of existence and uniqueness results that includes large data near a local Maxwellian regime with possibly infinite initial mass. We study the propagation of regularity using a recent estimate for the positive collision operator given in [3], by E. Carneiro and the authors, that permits to study such propagation without additional conditions on the collision kernel. Finally, an LpL^{p}-stability result (with 1p1\leq p\leq\infty) is presented assuming the aforementioned condition.Comment: 19 page

    Incidencia de tuberculosis osteoarticular en el área sanitaria del Hospital de León. 1997-2001

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    Introducción y objetivos: Nos proponemos en este trabajo estudiar la incidencia de tuberculosis en su forma osteoarticular en el área sanitaria del Hospital de León durante los años 1997 a 2001, ambos inclusive. Material y método: Dieciséis casos de tuberculosis osteoarticular confirmados por cultivo microbiológico y/o análisis anatomopatológico fueron incluidos. De ellos, cinco afectaron a columna vertebral, cuatro a rodilla y el resto a otras localizaciones más inusuales. Resultados: De las cinco columnas vertebrales afectadas, tres requirieron tratamiento quirúrgico para descomprimir y estabilizar. En una rodilla se realizó sinovectomía abierta y en otra por artroscopia. Se drenaron abscesos fríos en diferentes localizaciones. Todos los casos recibieron tratamiento médico. Se reflejan los diferentes resultados, desde la restitución ad integrum hasta la anquilosis. Discusión y conclusiones: La incidencia de tuberculosis osteoarticular en nuestra área sanitaria en el periodo 1997-2001 fue del 2% al 4% de todos los cascos de tuberculosis. Hubo una alta incidencia de localizaciones inusuales (muñeca, codo, sacroilíaca).Introduction: Current issue is to study the incidence of osteoarticular tuberculosis, within the sanitary area of the Hospital of Leon. Material and Method: Sixteen cases of osteoarticular tuberculosis confirmed by culture and pathological analysis were included. Five of them involved the raquis and knee. Another cases in unusual local sites. Results: Three of five raquis were managed by decompression and stabilization. One knee was treated by open synovectomy and another one by arthroscopy synovectomy. Cold abscesses were drained in different sites. All cases were treated with drugs. Different results are showed since restitutio ad integrum to anquilosis. Discussion: Osteoarticular tuberculosis incidence in our sanitary area between 1997 to 2001 was 2% to 4%. There was a high incidence for unusual localizations (wrist, elbow and sacroiliaca joints)

    A New Stability Criterion for IoT Systems in Smart Buildings: Temperature Case Study

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    The concept of smart cities emerged in the 1990s. Since then, smart buildings have become a closely interconnected element of smart cities. This type of building implements Internet of Things technology and control algorithms to monitor and control their indoor environment. The aim of this paper is to develop a new stability criterion method for smart building Internet of Things (IoT) systems, subject to external disturbances. The new stability criterion is going to optimize the operation of control algorithms since this criterion does not depend on the transmission function of the control algorithm but on the data collected by the IoT system. We present a new matrix called “Laplacian IoT matrix”, containing IoT network information associated with the graph of a smart building. The proposal is supported by the results of a numerical case study.This work was developed as part of “Virtual-Ledgers-Tecnologías DLT/Blockchain y Cripto-IOT sobre organizaciones virtuales de agentes ligeros y su aplicación en la eficiencia en el transporte de última milla”, ID SA267P18, project cofinanced by Junta Castilla y León, Consejería de Educación, and FEDER funds

    Nuestra experiencia con el minivástago femoral de disco a compresión y el cotilo Hedrocel (tantalio)

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    Durante los años 2000 a 2002 intervinimos 18 pacientes de artrosis o necrosis sintomática de cadera, con minivástago de fijación metafisiaria de Disco a Compresión (Sulzer) y cotilo monobloque de tantalio Hedrocel (Zimmer), con par de fricción alúmina-polietileno. La edad media de los pacientes fue de 46,7 años (rango 35-61), y el seguimiento medio de 42 meses. La valoración clínica se realizó con la escala de Merle D'Augbigné Postel obteniendo 38,8% de resultados excelentes, 22,2 de resultados buenos, 11,1% regulares y 27,4% malos (5 casos). Cuatro casos necesitaron reintervención por aflojamiento del tallo femoral. No hubo ningún fracaso del cotilo. La sustitución protésica de la cadera en los pacientes jóvenes requieren soluciones con la menor resección del hueso, pero este modelo de tallo femoral, no da un resultado satisfactorio, por lo que lo hemos abandonado.Between 2000 2002 we treated 18 patients with symptomatic osteoarthritis or osteonechrosis of hip, with uncemneted Thrust Plate Protesis (Sulzer) and tantalium acetabular componente Hedrocel (Zimmer), with ceramic-pol- yethylene pair. The average age of the patients was 46,7 years (range:35-61), and the average follow-up of 42 months. Clinical evaluation was done with Merle D'Augbigné Postel's scale obtaining 38,8 % of excellent results, 22,2 % of good results, 11,1 % fair and 27,4 % poor (5 cases). Four cases needed re-operation for loosening of the femoral stem. There was no failure of the acetabular component. The hip artrhroplasty in the young patients need solutions with the minor resection of bone, but this model of femoral stem does not give a satisfactory result, therefore we have abandoned it

    Arquitecturas de Referencia Edge Computing para la Industria 4.0: una revisión

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    Investigaciones recientes intentan demostrar que las arquitecturas de Edge Computing representan soluciones óptimas para minimizar la latencia, mejorar la privacidad y reducir el ancho de banda y los costos relacionados con los desarrollos para escenarios basados en el Internet de las Cosas (IoT), tales como: ciudades inteligentes, consumo eficiente de energía, agricultura inteligente o industria 4.0. Este trabajo es una revisión de las principales arquitecturas de referencia existentes de Edge Computing dirigidas a la Industria 4.0 propuestas por el Edge Computing Consortium, el Proyecto FAR-Edge Project, el Industrial Internet Consortium y finalmente por la asociación entre INTEL y SAP. Este trabajo incluye una comparación entre estas arquitecturas de referencia, así como sus características más importantes con el objetivo de proponer como trabajo futuro, el diseño de una Arquitectura de Referencia de Edge Computing aplicable a otros escenarios que no necesariamente estén relacionados con la industria 4.0

    Population Synthesis in the Blue IV: Accurate Model Predictions for Lick Indices and UBV Colors in Single Stellar Populations

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    [Abridged] We present new model predictions for 16 Lick absorption line indices from Hdelta through Fe5335, and UBV colors for single stellar populations (SPs) with ages ranging between 1 and 15 Gyr, [Fe/H] ranging from -1.3 to +0.3, and variable abundance ratios. We develop a method to estimate mean ages and abundances of Fe, C, N, Mg, and Ca that explores the sensitivity of the various indices to those parameters. When applied to high-S/N Galactic cluster data, the models match the clusters' elemental abundances and ages with high precision. Analyzing stacked SDSS spectra of early-type galaxies brighter than Lstar, we find mean luminosity-weighted ages of the order of ~ 8 Gyr and iron abundances slightly below solar. Abundance ratios, [X/Fe], are higher than solar, and correlate positively with galaxy luminosity. Nitrogen is the element whose abundance correlates the most strongly with luminosity, which seems to indicate secondary enrichment. This result may impose a lower limit of 50-200 Myr to the time-scale of star formation in early-type galaxies. Unlike in the case of clusters, in galaxies bluer Balmer lines yield younger ages than Hbeta. This age discrepancy is stronger for lower luminosity galaxies. We examine four scenarios to explain this trend. The most likely is the presence of small amounts of a young/intermediate-age SP component. Two-component models provide a better match to the data when the mass fraction of the young component is a few %. This result implies that star formation has been extended in early-type galaxies, and more so in less massive galaxies, lending support to the ``downsizing'' scenario. It also implies that SP synthesis models are capable of constraining not only the mean ages of SPs in galaxies, but also their age spread.Comment: To appear in the Astrophysical Journal Supplement Series. 55 Pages, using emulateapj5.sty. Full version, containing all (enlarged) figures can be found at http://www.astro.virginia.edu/~rps7v/Models/ms.pdf . A number of useful tables in the Appendix can be obtained in advance of publication by request to the autho

    State of the Art and System Overview

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    The promotion of changes in users’ behaviors with the aim of saving energy consumption in public buildings is a complex task that requires the use of multiple technologies. In this sense, context-aware technologies such as Wireless Sensor Networks and Real-Time Locating Systems, along with the use of Collaborative Learning, Virtual Organizations of Agents and Social Computing, provide a great potential for the development of serious games that foster the acquisition of good energy and healthy habits among workers and users in the public building. This paper presents the development of a serious game to change the users’ behaviors when using resources in public buildings using CAFCLA, a framework that allows the integration of multiple technologies that facilitate both context-awareness and social computing.info:eu-repo/semantics/publishedVersio

    The Star Formation History and the spatial distribution of stellar populations in the Ursa Minor Dwarf Spheroidal Galaxy

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    As a part of a project devoted to the study of the Ursa Minor dSph, the star formation history of the galaxy is presented in this paper. The analysis uses wide field photometry, encompassing about 1deg x 1deg (the total covered area being 0.75 deg^2), which samples the galaxy out to its tidal radius. Derivation of the SFH has been performed using the synthetic partial model technique. The resulting SFH shows that Ursa Minor hosts a predominantly old stellar population, with virtually all the stars formed earlier than 10 Gyr ago and 90% of them formed earlier than 13 Gyr ago. Nevertheless, Ursa Minor color-magnitude diagram shows several stars above the main, old turn-off forming a blue-plume (BP). If these stars were genuine, main-sequence stars, Ursa Minor would have maintained a low star formation rate extending up to 2 Gyr ago. However, several indications (relative amount and spatial distribution of BP stars and difficulty to retain processed gas) play against this possibility. In such context, the most reliable hypothesis is that BP stars are blue-stragglers originating in the old population, Ursa Minor hence remaining the only Milky Way dSph satellite to host a pure old stellar population. A marginally significant age gradient is detected, in the sense that stars in outer regions are slightly younger, in average. The distance of Ursa Minor, has been calculated using the magnitude of the horizontal-branch and a calibration based on Hipparcos data of main sequence sub-dwarfs. We estimated a distance d=76+/-4 Kpc, which is slightly larger than previous estimates. From the RGB color, we estimate a metallicity [Fe/H]=-1.9+/-0.2, in agreement with a previous spectroscopic determination. No metallicity gradients have been detected across the galaxy.Comment: 28 pages,3 tables, 10 figures, Accepted for publication in Astronomical Journa
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