311 research outputs found

    Leveraging on Digital Signage Networks to Bring Connectivity IOT Devices

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    The number of Internet-connected devices exceeds the world’s population by more than three times and this figure is expected to be doubled within the next five years. The Internet of Things is a concept that describes this trend and outlines certain aspects of design and functionality that new devices should incorporate for a successful integration into the Internet. In this respect, Digital Signage networks traditionally used for audiovisual media, accomplish many of the characteristics of the Internet of Things devices: interoperability, mobility, scalability and ubiquity, both in terms of access and control of devices and regarding the information they generate. This paper raises the power to employ a proposed Digital Signage network as a substrate to connect other types of devices that can benefit from the advantages of this kind of networks. For that aim, the main problems for this integration are discussed, mainly those related to the bidirectional tunneling scheme used in the proposed Digital Signage solution. The effects of this tunneling approach are analyzed in scenarios with bandwidth constraints, and different solutions are proposed. Tunneling performance in mobility is improved, to increase the amount of Internet of Things devices and applications that can benefit from this type of network. El número de dispositivos conectados a Internet supera actualmente a la población mundial por más de tres veces y se espera que esta cifra se duplique en los próximos cinco años. El Internet de las Cosas es un concepto que describe esta tendencia y perfila ciertos aspectos de diseño y funcionalidad que los nuevos dispositivos deben incorporar para lograr una integración exitosa en Internet. En este sentido, las redes digital signage utilizadas tradicionalmente para los medios de comunicación audiovisual cumplen muchas de las características requeridas en el contexto del Internet de las Cosas: interoperabilidad, movilidad, escalabilidad y ubicuidad; relativas tanto al acceso y control de dispositivos como a la información que estos generan. En este trabajo se plantea el poder de emplear la red digital signage propuesta como sustrato para poder conectar otros tipos de dispositivos para que así puedan aprovechar las ventajas de estas redes. Para ese fin, se discuten los principales problemas existentes en esta integración, prestando especial atención al esquema de túnel bidireccional utilizado en la solución digital signage propuesta. Los efectos de este enfoque de tunelación se analizan en escenarios con limitaciones de ancho de banda y se proponen diferentes soluciones. Con ello se consigue mejorar el rendimiento del túnel en movilidad, facilitando la integración de más dispositivos al Internet de las Cosas al permitir que puedan integrarse en este tipo de redes

    Continental shelf zones influenced by the suspended matter flows coming from Cadiz Bay

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    Due to the diversity of environments and hydrodynamics in Cadiz Bay, it is of interest to study the dynamics of sedimentary exchange between the coastal zones and continental shelf. The most abundant clay minerals on the floor of the continental shelf and Cadiz Bay, and in the particulate matter in suspension, are: illite, smectite, kaolinite + chlorite, and the interstratified clay minerals illite-smectite. The average concentration of suspended matter is 6.5 mg/l, the lowest (1.37 mg/l) being found on the inner shelf and in the inner zones of the bay less affected by currents and surge. The highest values (14 mg/l) are found in the outer bay, consistent with the distribution of muddy facies on the sea floor. The flow paths have been established from the local variations in the mineralogical associations found at the sampling stations, and by means of the alignments of the lowest values of the factor loadings at those stations most affected by the flows. The mineralogical similarity of the components of the clay fraction is related to the mixing action undergone by the components of the suspended matter reaching the bay from various sources, probably produced by the continuous action of the tidal ebb currents flowing from the inner sectors of the bay towards the continental shelf.El estudio de la dinámica de intercambio sedimentario entre las zonas litorales y la plataforma continental es de gran interés en el caso de la bahía de Cádiz, debido a su diversidad de ambientes y situaciones hidrodinámicas. Los minerales de la arcilla más abundantes en los fondos de la plataforma y la bahía, y en la materia en suspensión, son ilita, esmectita, caolinita + clorita e interestratificados ilita-esmectita. La concentración de materia sólida en suspensión indica un contenido promedio de 6,5 mg/l, apareciendo los mínimos (1,37 mg/l) en la plataforma interna y en zonas internas de la bahía no afectadas por corrientes y oleaje. Los valores más altos se dan en la bahía externa (14 mg/l), de acuerdo con la distribución de facies fangosas en el fondo. Las trayectorias de los flujos salientes se han establecido a partir de las variaciones locales de las asociaciones mineralógicas en las diferentes estaciones de muestreo, alineándose los valores más bajos de los factores en las estaciones más afectadas por la acción de los flujos. La similitud mineralógica de los componentes de la fracción arcilla en todos los ambientes se debe a la mezcla de componentes de la materia en suspensión que, desde diferentes fuentes, llegan a la bahía, y es favorecida por la acción de la corriente de reflujo mareal desde el sector más interno de la bahía a la plataforma continental.Instituto Español de Oceanografí

    The evolution of H{\sc ii} galaxies: Testing the bursting scenario through the use of self-consistent models

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    We have computed a series of realistic and self-consistent models of the emitted spectra of H{\sc ii} galaxies. Our models combine different codes of chemical evolution, evolutionary population synthesis and photoionization. The emitted spectrum of H{\sc ii} galaxies is reproduced by means of the photoionization code CLOUDY, using as ionizing spectrum the spectral energy distribution of the modelled H{\sc ii} galaxy, which in turn is calculated according to a Star Formation History (SFH) and a metallicity evolution given by a chemical evolution model that follows the abundances of 15 different elements. The contribution of emission lines to the broad-band colours is explicitly taken into account. The results of our code are compared with photometric and spectroscopic data of H{\sc ii} galaxies. Our technique reproduces observed diagnostic diagrams, abundances, equivalent width-colour and equivalent width-metallicity relations for local H{\sc ii} galaxies.Comment: 13 figures and 2 tables, accepted for publication in MNRAS Main Journa

    Wi-5: A Programming Architecture for Unlicensed Frequency Bands

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    We present Wi-5, a spectrum programming architecture for radio resource management in unlicensed frequency bands. It introduces a spectrum control plane that offers fine grained allocation of radio resources, flexible configuration of radio and wireless networking parameters, and continuous monitoring of the wireless network status. These features, along with the centralized nature of this architecture, can effectively address spectrum congestion which often occurs in unlicensed frequency bands. To demonstrate Wi-5’s capabilities, we show results obtained from emulating various use case scenarios on our open source proof-of-concept

    Symmetry preserving regularization with a cutoff

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    A Lorentz and gauge symmetry preserving regularization method is proposed in 4 dimension based on momentum cutoff. We use the conditions of gauge invariance or freedom of shift of the loop-momentum to define the evaluation of the terms carrying Lorentz indices, e.g. proportional to k_{\mu}k_{\nu}. The remaining scalar integrals are calculated with a four dimensional momentum cutoff. The finite terms (independent of the cutoff) are unambiguous and agree with the result of dimensional regularization.Comment: 12 pages, 1 figure, v2 references adde

    Analysis of the residual safety level in R/C slabs with severe joist corrosion

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    An analysis until the failure on a series of one-way slabs with severe corrosion at the lower reinforcement of the R/C joists is presented. Different positions in the slab and number of damaged joists have been studied, obtaining the residual safety assessment in cases of slabs damaged by flexural failure mechanisms. Since the boundary conditions have proved decisive for obtaining the behavior, the damaged slab has been evaluated as part of the entire building, as precisely as possible, taking into account the different phases of the construction process and deterioration in time, and the complex behavior of concrete, steel and masonry. The results of the proposed methodology are consistent with the pathology of the observed cases. As a result of this study the authors propose practical recommendations to help in making decisions about the magnitude of the intervention, always necessary in this type of pathology.Vercher Sanchis, JM.; Gil Benso, E.; Mas Tomas, MDLA.; Cubel Arjona, FJ. (2014). Analysis of the residual safety level in R/C slabs with severe joist corrosion. Journal of Performance of Constructed Facilities. 1-14. doi:10.1061/(ASCE)CF.1943-5509.0000608S11

    Comparative Analysis of the Volatile Fraction of Fruit Juice from Different Citrus Species

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    The volatile composition of fruit from four Citrus varieties (Powell Navel orange, Clemenules mandarine, and Fortune mandarine and Chandler pummelo) covering four different species has been studied. Over one hundred compounds were profiled after HS-SPME-GC-MS analysis, including 27 esters, 23 aldehydes, 21 alcohols, 13 monoterpene hydrocarbons, 10 ketones, 5 sesquiterpene hydrocarbons, 4 monoterpene cyclic ethers, 4 furans, and 2 aromatic hydrocarbons, which were all confirmed with standards. The differences in the volatile profile among juices of these varieties were essentially quantitative and only a few compounds were found exclusively in a single variety, mainly in Chandler. The volatile profile however was able to differentiate all four varieties and revealed complex interactions between them including the participation in the same biosynthetic pathway. Some compounds (6 esters, 2 ketones, 1 furan and 2 aromatic hydrocarbons) had never been reported earlier in Citrus juices. This volatile profiling platform for Citrus juice by HS-SPME-GC-MS and the interrelationship detected among the volatiles can be used as a roadmap for future breeding or biotechnological applications

    Challenges for Sustained Observing and Forecasting Systems in the Mediterranean Sea

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    The Mediterranean community represented in this paper is the result of more than 30 years of EU and nationally funded coordination, which has led to key contributions in science concepts and operational initiatives. Together with the establishment of operational services, the community has coordinated with universities, research centers, research infrastructures and private companies to implement advanced multi-platform and integrated observing and forecasting systems that facilitate the advancement of operational services, scientific achievements and mission-oriented innovation. Thus, the community can respond to societal challenges and stakeholders needs, developing a variety of fit-for-purpose services such as the Copernicus Marine Service. The combination of state-of-the-art observations and forecasting provides new opportunities for downstream services in response to the needs of the heavily populated Mediterranean coastal areas and to climate change. The challenge over the next decade is to sustain ocean observations within the research community, to monitor the variability at small scales, e.g., the mesoscale/submesoscale, to resolve the sub-basin/seasonal and inter-annual variability in the circulation, and thus establish the decadal variability, understand and correct the model-associated biases and to enhance model-data integration and ensemble forecasting for uncertainty estimation. Better knowledge and understanding of the level of Mediterranean variability will enable a subsequent evaluation of the impacts and mitigation of the effect of human activities and climate change on the biodiversity and the ecosystem, which will support environmental assessments and decisions. Further challenges include extending the science-based added-value products into societal relevant downstream services and engaging with communities to build initiatives that will contribute to the 2030 Agenda and more specifically to SDG14 and the UN's Decade of Ocean Science for sustainable development, by this contributing to bridge the science-policy gap. The Mediterranean observing and forecasting capacity was built on the basis of community best practices in monitoring and modeling, and can serve as a basis for the development of an integrated global ocean observing system

    Challenges for Sustained Observing and Forecasting Systems in the Mediterranean Sea

    Get PDF
    The Mediterranean community represented in this paper is the result of more than 30 years of EU and nationally funded coordination, which has led to key contributions in science concepts and operational initiatives. Together with the establishment of operational services, the community has coordinated with universities, research centers, research infrastructures and private companies to implement advanced multi-platform and integrated observing and forecasting systems that facilitate the advancement of operational services, scientific achievements and mission-oriented innovation. Thus, the community can respond to societal challenges and stakeholders needs, developing a variety of fit-for-purpose services such as the Copernicus Marine Service. The combination of state-of-the-art observations and forecasting provides new opportunities for downstream services in response to the needs of the heavily populated Mediterranean coastal areas and to climate change. The challenge over the next decade is to sustain ocean observations within the research community, to monitor the variability at small scales, e.g., the mesoscale/submesoscale, to resolve the sub-basin/seasonal and inter-annual variability in the circulation, and thus establish the decadal variability, understand and correct the model-associated biases and to enhance model-data integration and ensemble forecasting for uncertainty estimation. Better knowledge and understanding of the level of Mediterranean variability will enable a subsequent evaluation of the impacts and mitigation of the effect of human activities and climate change on the biodiversity and the ecosystem, which will support environmental assessments and decisions. Further challenges include extending the science-based added-value products into societal relevant downstream services and engaging with communities to build initiatives that will contribute to the 2030 Agenda and more specifically to SDG14 and the UN's Decade of Ocean Science for sustainable development, by this contributing to bridge the science-policy gap. The Mediterranean observing and forecasting capacity was built on the basis of community best practices in monitoring and modeling, and can serve as a basis for the development of an integrated global ocean observing system
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