3,580 research outputs found

    Collaborating with Theatre, Nature, and STEM: A Multigenerational Family Event

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    Family engagement can take many different formats, including community events. In this study, the researchers designed an event to encourage multigenerational family involvement using STEM (science, technology, engineering, and mathematics) and DAT (developmentally appropriate theater). The study was also designed in an outside environment to encourage interactions with nature and outdoor physical activity. The researchers found that families enjoyed the event and understood the academic and social benefits of nature and arts based education. Overall, this study continues a conversation focused on the importance of engaging families in nature and art based activities

    Designing TramMate:a context aware mobile system supporting use of public transportation

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    A general viscosity model of Campi Flegrei (Italy) melts

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    Viscosities of shoshonitic and latitic melts, relevant to the Campi Flegrei caldera magmas, have been experimentally determined at atmospheric pressure and 0.5 GPa, temperatures between 840 K and 1870 K, and H2O contents from 0.02 to 3.30 wt%. The concentric cylinder technique was employed at atmospheric pressure to determine viscosity of nominally anhydrous melts in the viscosity range of 101.5 - 103 Pa·s. The micropenetration technique was used to determine the viscosity of hydrous and anhydrous melts at atmospheric pressure in the high viscosity range (1010 Pa·s). Falling sphere experiments were performed at 0.5 GPa in the low viscosity range (from 100.35 to 102.79 Pa·s) in order to obtain viscosity data of anhydrous and hydrous melts. The combination of data obtained from the three different techniques adopted permits a general description of viscosity as a function of temperature and water content using the following modified VFT equation: where η is the viscosity in Pa·s, T the temperature in K, w the H2O content in wt%, and a, b, c, d, e, g are the VFT parameters. This model reproduces the experimental data (95 measurements) with a 1σ standard deviation of 0.19 and 0.22 log units for shoshonite and latite, respectively. The proposed model has been applied also to a more evolved composition (trachyte) from the same area in order to create a general model applicable to the whole compositional range of Campi Flegrei products. Moreover, speed data have been used to constrain the ascent velocity of latitic, shoshonitic, and trachytic melts within dikes. Using petrological data and volcanological information (geometrical parameters of the eruptive fissure and depth of magma storage), we estimate a time scale for the ascent of melt from 9 km to 4 km depth (where deep and shallow reservoirs, respectively, are located) in the order of few minutes. Such a rapid ascent should be taken into account for the hazard assessment in the Campi Flegrei area

    Detección de fuentes de emisión a partir de sensores perimetrales

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    El presente trabajo aborda la posible resolución de un problema de interés para varias disciplinas. entre las cuales se encuentra la fisica., dentro del marco de las redes neuronales. El problema a resolver. trata de la obtención de fuentes emisoras encerradas dentro de una región acotada circular del plano; sabiendo que el efecto de las fuentes sobre los sensores colocados en la curva frontera de la región es escalar, aditivo. y que se obtiene respecto de la magnitud de la fuente con una ley que va proporcional a la intensidad de esta e inversamente proporcional al cuadrado de la distancia. Para dicha resolución implementamos tres soluciones a partir del concepto de redes neuronales. La primera solución está basada en el aprendizaje competitivo. Con esta implementación logramos resolver el problema para dos fuentes, calculando tanto la posición como la intensidad de la misma. La segunda solución consiste en un perceptrón bícapa entrenado mediante back propagatíon. La red implementa el modelo directo del problema., de forma tal que sus pesos representan las posiciones e intensidades de las fuentes. El entrenamiento obtiene como resultado estas incógnitas. En la tercera solución implementamos un dispositivo que combina el ajuste competitivo de posiciones, con el ajuste de intensidades mediante un perceptrón. El perceptrón se ubica en capa de salida con función de activación lineal. La combinación de ambas redes (la competitiva y el perceptron) fue realizada según lo implementado en la primera solución, y ejecutando alternativamente una época de cada red, en donde las entradas del perceptrón serían los pesos de las unidades, ajustados por el inverso de su distancia a cada sensor. El problema así descripto, queda resuelto si logramos encontrar la magnitud y la posición de cada una de las fuentes encerradas, esto es conocer tres números para cada fuente. Vale señalar que la cantidad de fuentes. en principio, también es desconocida. Por esta razón en cada solución propuesta se realiza un sondeo con distintas cantidades de fuentes para conocer el alcance de la solución.Eje: Redes y sistemas inteligentesRed de Universidades con Carreras en Informática (RedUNCI

    Detección de fuentes de emisión a partir de sensores perimetrales

    Get PDF
    El presente trabajo aborda la posible resolución de un problema de interés para varias disciplinas. entre las cuales se encuentra la fisica., dentro del marco de las redes neuronales. El problema a resolver. trata de la obtención de fuentes emisoras encerradas dentro de una región acotada circular del plano; sabiendo que el efecto de las fuentes sobre los sensores colocados en la curva frontera de la región es escalar, aditivo. y que se obtiene respecto de la magnitud de la fuente con una ley que va proporcional a la intensidad de esta e inversamente proporcional al cuadrado de la distancia. Para dicha resolución implementamos tres soluciones a partir del concepto de redes neuronales. La primera solución está basada en el aprendizaje competitivo. Con esta implementación logramos resolver el problema para dos fuentes, calculando tanto la posición como la intensidad de la misma. La segunda solución consiste en un perceptrón bícapa entrenado mediante back propagatíon. La red implementa el modelo directo del problema., de forma tal que sus pesos representan las posiciones e intensidades de las fuentes. El entrenamiento obtiene como resultado estas incógnitas. En la tercera solución implementamos un dispositivo que combina el ajuste competitivo de posiciones, con el ajuste de intensidades mediante un perceptrón. El perceptrón se ubica en capa de salida con función de activación lineal. La combinación de ambas redes (la competitiva y el perceptron) fue realizada según lo implementado en la primera solución, y ejecutando alternativamente una época de cada red, en donde las entradas del perceptrón serían los pesos de las unidades, ajustados por el inverso de su distancia a cada sensor. El problema así descripto, queda resuelto si logramos encontrar la magnitud y la posición de cada una de las fuentes encerradas, esto es conocer tres números para cada fuente. Vale señalar que la cantidad de fuentes. en principio, también es desconocida. Por esta razón en cada solución propuesta se realiza un sondeo con distintas cantidades de fuentes para conocer el alcance de la solución.Eje: Redes y sistemas inteligentesRed de Universidades con Carreras en Informática (RedUNCI

    Retrieving magma composition from TIR spectra: implications for terrestrial planets investigations

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    Emissivity and reflectance spectra have been investigated on two series of silicate glasses, having compositions belonging to alkaline and subalkaline series, covering the most common terrestrial igneous rocks. Glasses were synthesized starting from natural end-members outcropping at Vulcano Island (Aeolian Islands, Italy) and on Snake River Plain (USA). Results show that the shift of the spectra, by taking Christiansen feature (CF) as a reference point, is correlated with SiO2 content, the SCFM factor and/or the degree of polymerization state via the NBO/T and temperature. The more evolved is the composition, the more polymerized the structure, the shorter the wavelength at which CF is observable. CF shift is also dependent on temperature. The shape of the spectra discriminates alkaline character, and it is related to the evolution of Qn structural units. Vulcano alkaline series show larger amount of Q4 and Q3 species even for mafic samples compared to the subalkaline Snake River Plain series. Our results provide new and robust insights for the geochemical characterization of volcanic rocks by remote sensing, with the outlook to infer origin of magmas both on Earth as well as on terrestrial planets or rocky bodies, from emissivity and reflectance spectra

    Cooling history and emplacement of a pyroxenitic lava as proxy for understanding Martian lava flows

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    Terrestrial analogues are often investigated to get insights into the geological processes occurring on other planetary bodies. Due to its thickness and petrological similarities, the pyroxenitic layer of the 120m-thick magmatic pile Theo’s Flow (Archean Abitibi greenstone belt Ontario, Canada), has always been regarded as the terrestrial analogue for Martian nakhlites. However, its origin and cooling history and, as a consequence those of nakhlites, have always been a matter of vigorous debate. Did this lava flow originate from a single magmatic event similar to those supposed to occur on Mars or do the different units derive from multiple eruptions? We demonstrate, by a combination of geothermometric constraints on augite single crystals and numerical simulations, that Theo’s Flow has been formed by multiple magma emplacements that occurred at different times. This discovery supports the idea that the enormous lava flows with similar compositions observed on Mars could be the result of a process where low viscosity lavas are emplaced during multiple eruptions. This has profound implications for understanding the multiscale mechanisms of lava flow emplacement on Earth and other planetary bodies

    Q methodology and a Delphi poll: a useful approach to researching a narrative approach to therapy

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    Q methodology and a Delphi poll combined qualitative and quantitative methods to explore definitions of White and Epston's (1990) narrative approach to therapy among a group of UK practitioners. A Delphi poll was used to generate statements about narrative therapy. The piloting of statements by the Delphi panel identified agreement about theoretical ideas underpinning narrative therapy and certain key practices. A wider group of practitioners ranked the statements in a Q sort and made qualitative comments about their sorting. Quantitative methods (principal components analysis) were used to extract eight accounts of narrative therapy, five of which are qualitatively analysed in this paper. Agreement and differences were identified across a range of issues, including the social construction of narratives, privileging a political stance or narrative techniques and the relationship with other therapies, specifically systemic psychotherapy. Q methodology, combined with the Delphi poll, was a unique and innovative feature of this study

    Mashups: An Approach to Overcoming the Business/IT Gap in Service-Oriented Architectures

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    For quite a long time already, great importance has been attached to the concept of Service-Oriented Architectures for future IT-architectures. However, a major challenge in implementing this concept lies in the gap between the functional department and IT department. Mashups, an architecture also based on services, try to avoid this gap by letting the user himself integrate the services. The following article analyzes similarities and differences between both architecture approaches, and explains to what extent and in which cases Mashups could complement a Service-Oriented Architecture

    Spectral Lags and the Lag-Luminosity Relation: An Investigation with Swift BAT Gamma-ray Bursts

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    Spectral lag, the time difference between the arrival of high-energy and low-energy photons, is a common feature in Gamma-ray Bursts (GRBs). Norris et al. 2000 reported a correlation between the spectral lag and the isotropic peak luminosity of GRBs based on a limited sample. More recently, a number of authors have provided further support for this correlation using arbitrary energy bands of various instruments. In this paper we report on a systematic extraction of spectral lags based on the largest Swift sample to date of 31 GRBs with measured redshifts. We extracted the spectral lags for all combinations of the standard Swift hard x-ray energy bands: 15-25 keV, 25-50 keV, 50-100 keV and 100-200 keV and plotted the time dilation corrected lag as a function of isotropic peak luminosity. The mean value of the correlation coefficient for various channel combinations is -0.68 with a chance probability of ~ 0.7 x 10^{-3}. In addition, the mean value of the power-law index is 1.4 +/- 0.3. Hence, our study lends support for the existence of a lag-luminosity correlation, albeit with large scatter.Comment: 19 Pages, 11 Figures and 5 Tables; Accepted to The Astrophysical Journa
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