454 research outputs found

    Desarrollo y aplicación del algoritmo de Optimización basado en Colonia de Hormigas (ACO) para la resolución del Problema del Viajante Asimétrico (ATSP)

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    Los algoritmos evolutivos, concretamente los basados en Colonia de Hormigas, ACO, están cobrando cada vez más importancia en el campo de la metaheurística, así como su aplicación para la resolución de problemas de optimización combinatoria. Uno de los problemas más comunes y difíciles de resolver que se clasifica como NP-duro, es el Problema del Viajante, TSP. El interés en el estudio de las técnicas metaheurísticas para la resolución de este problema radica, principalmente, en el gran número de aplicaciones prácticas en las que se encuentra. El presente documento recoge, explícitamente, el desarrollo y aplicación de un algoritmo ACO para la resolución del problema del viajante asimétrico, ATSP, cuyo fin es encontrar una solución que, satisfaciendo las condiciones iniciales del problema, proporcione una ruta o circuito cerrado cuya longitud sea la mínima. Para ello, se realizarán una serie de pruebas, a través de las cuales se obtendrán resultados que, posteriormente, se evaluarán y valorarán mediante el uso de técnicas estadísticas adecuadas.Departamento de Organización de Empresas y Comercialización e Investigación de MercadosGrado en Ingeniería en Organización Industria

    Maritime Data Transfer Protocol (MDTP): A Proposal for a Data Transmission Protocol in Resource-Constrained Underwater Environments Involving Cyber-Physical Systems

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    The utilization of autonomous maritime vehicles is becoming widespread in operations that are deemed too hazardous for humans to be directly involved in them. One of the ways to increase the productivity of the tools used during missions is the deployment of several vehicles with the same objective regarding data collection and transfer, both for the benefit of human staff and policy makers. However, the interchange of data in such an environment poses major challenges, such as a low bandwidth and the unreliability of the environment where transmissions take place. Furthermore, the relevant information that must be sent, as well as the exact size that will allow understanding it, is usually not clearly established, as standardization works are scarce in this domain. Under these conditions, establishing a way to interchange information at the data level among autonomous maritime vehicles becomes of critical importance since the needed information, along with the size of the transferred data, will have to be defined. This manuscript puts forward the Maritime Data Transfer Protocol, (MDTP) a way to interchange standardized pieces of information at the data level for maritime autonomous maritime vehicles, as well as the procedures that are required for information interchange.SWARMs (Smart and Networking Underwater Robots in Cooperation Meshes) 1034 European research project. It is under Grant Agreement 1035 n.662107-SWARMs-ECSEL-2014-1 and is being partially supported by the Spanish Ministry of Economy and Competitiveness (Ref: PCIN-2014-022-C02-02) and the ECSEL JU

    2015 Hawaiian Digital Resource Series

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    Presentation slidesWith so much information on-line it is hard to grasp the depth and potential of some resources. In an effort to highlight the hard work of many dedicated individuals who are committed to preserving and perpetuating Hawaiian knowledge, five guest speakers representing four different digital repositories were invited to the Kahuku Public and School Library to present their tools. With the kokua of LIS classmates, staff and community support, the Hawaiian Digital Resource Series successfully increased the awareness of 'Ulu 'Ulu - Henry Giugni Moving Image Archive, Papakilo, Kipuka, and Ulukau in Ko'olauloa

    A Comparison of Methods Used to Define the Phenolic Content and Antioxidant Activity of Croatian Wines

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    Concentrations of phenolic antioxidants and antioxidant activities were determined for three different vintages of red varietal Plavac mali wines (Grgich), white varietal Pošip wines (Grgich) and white varietal Žlahtina wines (Gršković). All three mentioned cultivars (Vitis vinifera L.) are well exploited in vineyards along the Croatian coast. Two different tests, the spectrophotometric Folin-Ciocalteau test and redox derivative potentiometric titration with electrogenerated chlorine, were used to quantify phenolic antioxidants and express them in gallic acid equivalents. The sequence of wines obtained by the two methods, ranked according to the increasing phenolic content, was comparable. Among all the tested wines, Plavac mali of the vintage 2003 showed the highest phenol content of ~5 g/L. As expected, due to the lack of anthocyanins and other pigments present in red wines, all six white wines showed approximately ten times lower phenolic levels in comparison with red wines, averaging between 190–380 mg/L. This study demonstrates the utilization of quick and reliable analytical techniques, spectrophotometry and derivative potentiometric titration, in quantification of wine phenolics. The change in free radical scavenging ability of the same set of wines was evaluated according to the Brand-Williams assay. The results show, on average, eight times higher free radical scavenging ability of red wines. Also, a slight decrease in the free radical scavenging ability of the older vintage white wines was observed, while the antioxidant activities of the older vintage red wines (Plavac mali) were slightly higher, due to formation of condensed tannins with time

    A Comparison of Methods Used to Define the Phenolic Content and Antioxidant Activity of Croatian Wines

    Get PDF
    Concentrations of phenolic antioxidants and antioxidant activities were determined for three different vintages of red varietal Plavac mali wines (Grgich), white varietal Pošip wines (Grgich) and white varietal Žlahtina wines (Gršković). All three mentioned cultivars (Vitis vinifera L.) are well exploited in vineyards along the Croatian coast. Two different tests, the spectrophotometric Folin-Ciocalteau test and redox derivative potentiometric titration with electrogenerated chlorine, were used to quantify phenolic antioxidants and express them in gallic acid equivalents. The sequence of wines obtained by the two methods, ranked according to the increasing phenolic content, was comparable. Among all the tested wines, Plavac mali of the vintage 2003 showed the highest phenol content of ~5 g/L. As expected, due to the lack of anthocyanins and other pigments present in red wines, all six white wines showed approximately ten times lower phenolic levels in comparison with red wines, averaging between 190–380 mg/L. This study demonstrates the utilization of quick and reliable analytical techniques, spectrophotometry and derivative potentiometric titration, in quantification of wine phenolics. The change in free radical scavenging ability of the same set of wines was evaluated according to the Brand-Williams assay. The results show, on average, eight times higher free radical scavenging ability of red wines. Also, a slight decrease in the free radical scavenging ability of the older vintage white wines was observed, while the antioxidant activities of the older vintage red wines (Plavac mali) were slightly higher, due to formation of condensed tannins with time

    Predicting invasion success in complex ecological networks

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    A central and perhaps insurmountable challenge of invasion ecology is to predict which combinations of species and habitats most effectively promote and prevent biological invasions. Here, we integrate models of network structure and nonlinear population dynamics to search for potential generalities among trophic factors that may drive invasion success and failure. We simulate invasions where 100 different species attempt to invade 150 different food webs with 15–26 species and a wide range (0.06–0.32) of connectance. These simulations yield 11 438 invasion attempts by non-basal species, 47 per cent of which are successful. At the time of introduction, whether or not the invader is a generalist best predicts final invasion success; however, once the invader establishes itself, it is best distinguished from unsuccessful invaders by occupying a lower trophic position and being relatively invulnerable to predation. In general, variables that reflect the interaction between an invading species and its new community, such as generality and trophic position, best predict invasion success; however, for some trophic categories of invaders, fundamental species traits, such as having the centre of the feeding range low on the theoretical niche axis (for non-omnivorous and omnivorous herbivores), or the topology of the food web (for tertiary carnivores), best predict invasion success. Across all invasion scenarios, a discriminant analysis model predicted successful and failed invasions with 76.5 per cent accuracy for properties at the time of introduction or 100 per cent accuracy for properties at the time of establishment. More generally, our results suggest that tackling the challenge of predicting the properties of species and habitats that promote or inhibit invasions from food web perspective may aid ecologists in identifying rules that govern invasions in natural ecosystems

    The disease-protective complement factor H allotypic variant Ile62 shows increased binding affinity for C3b and enhanced cofactor activity

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    38 p.- 7 fig.Mutations and polymorphisms in the gene encoding factor H (CFH) have been associated with atypical haemolytic uraemic syndrome, dense deposit disease and age-related macular degeneration. The disease-predisposing CFH variants show a differential association with pathology that has been very useful to unravel critical events in the pathogenesis of one or other disease. In contrast, the factor H (fH)-Ile62 polymorphism confers strong protection to all three diseases. Using ELISA-based methods and surface plasmon resonance analyses, we show here that the protective fH-Ile62 variant binds more efficiently to C3b than fH-Val62 and competes better with factor B in proconvertase formation. Functional analyses demonstrate an increased cofactor activity for fH-Ile62 in the factor I-mediated cleavage of fluid phase and surface-bound C3b; however, the two fH variants show no differences in decay accelerating activity. From these data, we conclude that the protective effect of the fH-Ile62 variant is due to its better capacity to bind C3b, inhibit proconvertase formation and catalyze inactivation of fluid-phase and surface-bound C3b. This demonstration of the functional consequences of the fH-Ile62 polymorphism provides relevant insights into the complement regulatory activities of fH that will be useful in disease prediction and future development of effective therapeutics for disorders caused by complement dysregulationThis work was supported by MRC Project Grant Ref 84908 (to C.L.H. and B.P.M.), Ministerio de Ciencia e Innovación Ref SAF 2005-00913 (to S.R.deC.) the CIBER de Enfermedades Raras and Fundación Renal Iñigo Alvarez de Toledo (to S.R.deC.).Peer reviewe

    Desarrollo de un Índice Maestro de Pacientes utilizando estándares y software open source

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    Es fundamental, que todo efector relacionado con la salud que tenga sistemas informáticos implemente procesos que permitan identificar en forma única a una persona evitando los problemas relacionados con la duplicación de pacientes. Por este motivo, en este trabajo se presenta una propuesta de desarrollo de un Índice Maestro de Pacientes (IMP) utilizando estándares y centrado en la implementación del módulo de búsquedas y auditoría. El objetivo fundamental es definir una arquitectura utilizando software open source que permita realizar los procesos necesarios para lograr el objetivo de evitar y corregir la duplicación de los datos de los pacientes aumentando la calidad de estos.Sociedad Argentina de Informática e Investigación Operativa (SADIO
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