Experimental phase functions of mm-sized cosmic dust grains

We present experimental phase functions of three types of millimeter-sized dust grains consisting of enstatite, quartz and volcanic material from Mount Etna, respectively. The three grains present similar sizes but different absorbing properties. The measurements are performed at 527 nm covering the scattering angle range from 3 to 170 degrees. The measured phase functions show two well defined regions i) soft forward peaks and ii) a continuous increase with the scattering angle at side- and back-scattering regions. This behavior at side- and back-scattering regions are in agreement with the observed phase functions for the Fomalhaut and HR 4796A dust rings. Further computations and measurements (including polarization) for millimeter sized-grains are needed to draw some conclusions about the fluffy or compact structure of the dust grains

Interactive Embodied Agents for Cultural Heritage and Archaeological presentations

[EN] In this paper, Maxine, a powerful engine to develop applications with embodied animated agents is presented. The engine, based on the use of open source libraries, enables multimodal real-time interaction with the user: via text, voice, images and gestures. Maxine virtual agents can establish emotional communication with the user through their facial expressions, the modulation of the voice and expressing the answers of the agents according to the information gathered by the system: noise level in the room, observer’s position, emotional state of the observer, etc. Moreover, the user’s emotions are considered and captured through images. For the moment, Maxine virtual agents have been used as virtual presenters for Cultural Heritage and Archaeological shows.This work has been partially financed by the Spanish “Dirección General de Investigación'' (General Directorate of Research), contract number Nº TIN2007-63025, and by the Regional Government of Aragon through the WALQA agreement.Seron, F.; Baldassarri, S.; Cerezo, E. (2010). Interactive Embodied Agents for Cultural Heritage and Archaeological presentations. Virtual Archaeology Review. 1(1):181-184. https://doi.org/10.4995/var.2010.5143OJS18118411BALDASSARRI, S., CEREZO, E., SERON, F. (2007): An open source engine for embodied animated agents.In Proc. Congreso Español de Informática Gráfica: CEIG'07, pp. 89-98.BERRY, D.et al, (2005). Evaluating a realistic agent in an advice-giving task. In International Journal in Human-Computer Studies, Nº 63, pp. 304-327. http://dx.doi.org/10.1016/j.ijhcs.2005.03.006BOFF, E. et al, (2005). An affective agent-based virtual character for learning environments. Proceedings of the Wokshop on Motivation and Affect in Educational Software, 12th International Conference on Artificial Intelligence in Education. Amsterdam, Holland, pp 1-8.BURLESON, W. et al, (2004). A Platform for Affective Agent Research. Proceedings of the Workshop on Empathetic Agents, International Conference on Autonomous Agents and Multiagent Systems, New York, USA.CEREZO, E., BALDASSARRI, S., SERON, F. (2007): Interactive agents for multimodal emotional user interaction. In Proc. of IADIS International Conference Interfaces and Human Computer Interaction, pp. 35-42.CASELL, J. et al (eds), (2000), in Embodied Conversational Agents. MIT Press, Cambridge, USA.El-NASR, M. S. et al, (1999). A PET with Evolving Emotional Intelligence. Proceedings of the 3rd Annual Conference on Autonomous Agents. Seattle, USA, pp. 9 - 15. http://dx.doi.org/10.1145/301136.301150GRAESSER, A. et al, (2005). AutoTutor: An Intelligent tutoring system with mixed-initiative dialogue. In IEEE Transactions on Education, Vol. 48, Nº 4, pp. 612-618. http://dx.doi.org/10.1109/TE.2005.856149KASAP, Z. and N. MAGNENAT-THALMANN (2007): "Intelligent virtual humans with autonomy and personality: State-of-the-art", in IntelligentDecision Technologies. IOS PressMARSELLA S. C et al, (2000). Interactive Pedagogical Drama. Proceedings of the 4th International Conference on Autonomous Agents. Barcelona, Spain, pp. 301-308. http://dx.doi.org/10.1145/336595.337507MIGNONNEAU, L. and SOMMERER, C. (2005). Designing emotional, methaforic, natural and intuitive interfaces for interactive art, edutainment and mobile communications, in Computer & Graphics, Vol. 29, pp. 837-851.PRENDINGER, H. and ISHIZUKA, M., (2005). The Empathic Companion: A Character-Based Interface that Addresses Users' Affective States. In Applied Artificial Intelligence, Vol.19, pp.267-285. http://dx.doi.org/10.1080/08839510590910174ROSIS, F. et al, (2003). From Greta's mind to her face: modelling the dynamics of affective status in a conversational embodied agent. In International Journal of Human-computer Studies. Special Issue on Applications of Affective Computing in HCI, Vol 59, pp 81-118. http://dx.doi.org/10.1016/s1071-5819(03)00020-xYUAN, X. and CHEE, S. (2005). Design and evaluation of Elva: an embodied tour guide in an interactive virtual art gallery. In Computer Animation and Virtual Worlds, Vol. 16, pp.109-119. http://dx.doi.org/10.1002/cav.6

ECONOMIC EFFECTS OF CO-EXISTENCE MEASURES IN MAIZE CROP AND SEED PRODUCTION - A CASE STUDY OF FRANCE

Paper prepared for presentation at the Second International Conference on Coexistence between Genetically Modified (GM) and non-GM based Agricultural Supply Chains (GMCC) Montpellier (France), 14th and 15th November 2005Genetic engineering, GMO, Maize, Co-existence, Agricultural and Food Policy, L51, O32,

¿Son útiles los programas de intervención? ¿Cómo evaluar su eficacia?

Desde los primeros informes nacionales sobre la situación del bullying en las aulas españolas (AA.VV., 2000; 2006) se vienen aplicando estrategias de prevención y/o intervención orientadas a reducir su incidencia. Las administraciones públicas instaron a los centros escolares a elaborar estrategias de control de la conducta violenta, así encontramos los llamados Planes de Convivencia, que se han desarrollado en la práctica totalidad de los centros. Paralelamente surgieron programas específicos con carácter aplicado e investigador. A los que cabe añadir el reciente decreto que regula la convivencia en los centros escolares, que recoge un listado de medidas a aplicar según el tipo de “falta” perpetrada, y señala la necesidad de adoptar medidas educativas. Ante este panorama, entendemos pertinente una reflexión sistemática del alcance de los programas implementados. Encontramos algunas directrices comunes: la necesaria implicación del conjunto de la comunidad educativa, incidir en la mejora del clima social de grupo-aula y en la atención educativa y psicológica a los directamente implicados (agresores y víctimas). A pesar de éstos esfuerzos la reducción de la violencia relacional en las aulas apenas es apreciable (Cerezo, 2009; Garaigordobil y Oñederra, 2008), el último informe de Save the children (2016), todavía apunta niveles de bullying muy preocupantes. Entonces, ¿para qué sirven estos programas de intervención sobre la violencia escolar?, ¿qué están aportando los Planes de Convivencia a su reducción? Es por ello que indagamos hasta qué punto las medidas sobre convivencia están siendo eficaces y cuáles son las principales causas por las que los niveles de violencia relacional no disminuyen. Entre estas causas cabe apuntar: desconocimiento general sobre las medidas adoptadas; escasa participación e implicación familiar, escasa formación del profesorado y precariedad de los equipos de orientación, a lo que hay que añadir el carácter puntual de la mayoría de las intervenciones

Thermal stability and mechanical property of polymer layered graphite oxide composites

Polymer composites formed from layered fillers with high surface volume ratio show enhanced reinforcement. Graphite oxide is a high modulus material that can be separated into thin layers with high surface area. The aim of this study is to prepare polymer layered graphite oxide composites using functionalised polyolefin to enhance compatibility with various forms of layered graphite oxide in varying concentration. Functionalised polyolefins reinforced with layered graphite oxides and expanded graphite oxides were prepared using solution blending and melt blending methods. Three different mixing methods with varying shear intensity were employed to prepare polymer layered graphite oxide composites. The crystalline structure, thermal and mechanical properties of the prepared polymer layered graphite oxide composites was studied. Oxidised graphite prepared from the Staudenmaier method and its exfoliated form were dispersed in poly(ethylene-co-methyl acrylate-co-acrylic acid) (EMAA) via solution blending to prepare EMAA layered composites. The thermal stability was determined using thermogravimetric analysis. The EMAA layered composites showed higher thermal stability in comparison with pure EMAA. The mechanical properties of these EMAA layered composites were determined through dynamic mechanical analysis. Shear modulus, yield stress and storage modulus of EMAA in the presence of graphite oxide fillers decreased. A solution blending method was used to prepare poly(propylene-grafted-maleic anhydride) layered expanded graphite oxide composites (PPMA-EGO). Two types of PPMA-EGO were prepared using different mixing methods - low and high shear were employed. The effects of preparative mixing methods on the PPMA-EGO properties were investigated. The mechanical properties of PPMA-EGO obtained from dynamic mechanical analysis indicated that EGO had a reinforcing effect on the elastic behaviour of PPMA-EGO. This is due to strong interfacial adhesion between PPMA and EGO as a result of hydrogen bonding. The elastic behaviour of PPMA-EGO was affected by the surface area of graphite flakes. Low sheared PPMA-EGO elastic behaviour was found to be higher compared with that of high sheared PPMA-EGO. A melt blending method was used to prepare PPMA-EGO with varying EGO concentration. The interconnected network structure of EGO in the PPMA-EGO was not observed as shown by its scanning electron microscopy images. Thermogravimetric analysis of PPMA-EGO indicates increased decomposition temperature of the PPMA matrix. Dynamic mechanical analysis showed enhanced storage modulus of PPMA-EGO. The maximum elastic modulus of PPMA-EGO was observed at 3 %wt of EGO. The electrical conductivity of PPMA-EGO was measured only for EGO concentrations above 2 %wt. The EGO concentration was found to be the most critical factor in the enhancement of the electrical conductivity of PPMA-EGO. Wide angle X-ray diffraction analysis of all polymer layered graphite oxide composites revealed no change in interlayer spacing of graphite layers, indicating the absence of EMAA intercalation in the graphite layers. The crystallisation temperature and crystallinity of all polymer layered graphite oxide composites were determined using differential scanning calorimetry. The results indicated that graphite oxide and expanded graphite oxides acted as nucleating agents in inducing the crystallisation of functionalised polyolefin in the layered composites. However, the degree of crystallinity of functionalised polyolefin decreased in the layered composites

Optical microtopographic inspection of asphalt pavement surfaces

Microtopographic and rugometric characterization of surfaces is routinely and effectively performed non-invasively by a number of different optical methods. Rough surfaces are also inspected using optical profilometers and microtopographer. The characterization of road asphalt pavement surfaces produced in different ways and compositions is fundamental for economical and safety reasons. Having complex structures, including topographically with different ranges of form error and roughness, the inspection of asphalt pavement surfaces is difficult to perform non-invasively. In this communication we will report on the optical non-contact rugometric characterization of the surface of different types of road pavements performed at the Microtopography Laboratory of the Physics Department of the University of Minho.This work was partially financed project PEst-OE/ECI/UI4047/2014 supported by Portuguese Foundation for Science and Technology.info:eu-repo/semantics/publishedVersio

Autonomía y orientación en el Espacio Europeo de Educación Superior mediante el portafolio y la tutoría

En el nuevo rol del profesor y del estudiante universitario, según el cual el primero asume funciones de guía, orientador, asesor y facilitador de recursos para el aprendizaje activo del segundo, se le da más importancia al aprendizaje que a la enseñanza. En este trabajo mostramos la percepción que tienen 290 estudiantes de distintas especialidades de Magisterio y Fisioterapia sobre el uso del portafolios y de la tutoría como elementos de interés para los procesos de innovación docente (Espacio Europeo de Educación Superior). Para tal fin se ha pasado un cuestionario, efectuándose un análisis descriptivo y comparativo, obteniendo evidencias de interés

On the practical usefulness of the Hardware Efficient Ansatz

Variational Quantum Algorithms (VQAs) and Quantum Machine Learning (QML) models train a parametrized quantum circuit to solve a given learning task. The success of these algorithms greatly hinges on appropriately choosing an ansatz for the quantum circuit. Perhaps one of the most famous ansatzes is the one-dimensional layered Hardware Efficient Ansatz (HEA), which seeks to minimize the effect of hardware noise by using native gates and connectives. The use of this HEA has generated a certain ambivalence arising from the fact that while it suffers from barren plateaus at long depths, it can also avoid them at shallow ones. In this work, we attempt to determine whether one should, or should not, use a HEA. We rigorously identify scenarios where shallow HEAs should likely be avoided (e.g., VQA or QML tasks with data satisfying a volume law of entanglement). More importantly, we identify a Goldilocks scenario where shallow HEAs could achieve a quantum speedup: QML tasks with data satisfying an area law of entanglement. We provide examples for such scenario (such as Gaussian diagonal ensemble random Hamiltonian discrimination), and we show that in these cases a shallow HEA is always trainable and that there exists an anti-concentration of loss function values. Our work highlights the crucial role that input states play in the trainability of a parametrized quantum circuit, a phenomenon that is verified in our numerics