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Thermoplastic Starch-based Composites Reinforced with Rape Fibers: Water Uptake and Thermomechanical Properties

  • Espigulé, Eva
  • Puigvert Colomer, Xavier
  • Vilaseca Morera, Fabiola
  • Méndez González, José Alberto
  • Mutjé Pujol, Pere
  • Gironès i Molera, Jordi
Fully biodegradable composite materials were obtained through reinforcement of a commercially available thermoplastic starch (TPS) matrix with rapeseed fibers (RSF). The influence of reinforcement content on the water sorption capacity, as well as thermal and thermo-mechanical properties of composites were evaluated. Even though the hydrophilic character of natural fibers tends to favor the absorption of water, results demonstrated that the incorporation of RSF did not have a significant effect on the water uptake of the composites. DSC experiments showed that fibers restricted the mobility of the starch macromolecules from the TPS matrix, hence reducing their capacity to crystallize. The viscoelastic behaviour of TPS was also affected, and reinforced materials presented lower viscous deformation and recovery capacity. In addition, the elasticity of materials was considerably diminished when increasing fiber content, as evidenced in the TMA and DMTA measurements
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Micromechanics of Mechanical, Thermomechanical, and Chemi-Thermomechanical Pulp from Orange Tree Pruning as Polypropylene Reinforcement: A Comparative Study

  • Reixach Corominas, Rafel
  • Franco Marquès, Elena
  • El Mansouri, Nour-Eddine
  • Ramírez de Cartagena Bisbe, Francisco
  • Arbat Pujolràs, Gerard
  • Espinach Orús, Xavier
  • Mutjé Pujol, Pere
This work explores the use of mechanical (MP), thermomechanical (TMP), and chemi-thermomechanical (CTMP) pulps from orange tree pruning fibers (OPF) as reinforcing elements of polypropylene (PP) composites. Due to the nature of the natural fibers, the use of a coupling agent is needed to attain a good interface and to prevent fiber slippage from the matrix. The main objective of the present work was to investigate the orientation factor, the interfacial shear strength, and the intrinsic strength of the OPF. Coupled and non-coupled composites were formulated and tested, optimizing the coupling agent content with the objective of maximizing the tensile strength of the composites. Hirsch and Kelly-Tyson models and the Bowyer-Bader methodology were used to compute the micromechanic properties. The contribution of subcritical, supercritical fibers, and matrix were also calculated, The authors are grateful for the support of the EMCI - Ministerio de Ciencia e Innovacion (MICINN) for funding the research by the specific Research Program CTQ2010-21660-C03-03
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All-Optical Label Stacking: Easing the Trade-offs Between Routing and Architecture Cost in All-Optical Packet Switching

  • Solano Donado, Fernando
  • Caenegem, Ruth van
  • Colle, Didier
  • Marzo i Lázaro, Josep Lluís
  • Pickavet, Mario
  • Fabregat Gesa, Ramon
  • Demeester, Piet
All-optical label swapping (AOLS) forms a key technology towards the implementation of all-optical packet switching nodes (AOPS) for the future optical Internet. The capital expenditures of the deployment of AOLS increases with the size of the label spaces (i.e. the number of used labels), since a special optical device is needed for each recognized label on every node. Label space sizes are affected by the way in which demands are routed. For instance, while shortest-path routing leads to the usage of fewer labels but high link utilization, minimum interference routing leads to the opposite. This paper studies all-optical label stacking (AOLStack), which is an extension of the AOLS architecture. AOLStack aims at reducing label spaces while easing the compromise with link utilization. In this paper, an integer lineal program is proposed with the objective of analyzing the softening of the aforementioned trade-off due to AOLStack. Furthermore, a heuristic aiming at finding good solutions in polynomial-time is proposed as well. Simulation results show that AOLStack either a) reduces the label spaces with a low increase in the link utilization or, similarly, b) uses better the residual bandwidth to decrease the number of labels even more
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Private micro-irrigation costs using reclaimed water

  • Pujol Planella, Joan
  • Duran i Ros, Miquel
  • Arbat Pujolràs, Gerard
  • Ramírez de Cartagena Bisbe, Francisco
  • Puig Bargués, Jaume
The cost of reusing water in micro-irrigation at the field level has not been studied in depth although the use of effluents in agriculture is a viable alternative in areas where water is scarce or there is intense competition for its use. The aim of the present study is to analyse the private costs of water reuse in micro-irrigation in an experimental plot. This analysis is intended to provide information about the decision a farmer would make when the choice to use conventional or reclaimed water is guided by cost criteria. The components of the total costs of different combinations of four types of filters and five emitters that can be installed in micro-irrigation systems using reclaimed water have been studied with the data obtained from an experimental plot in conditions similar to those of fruit orchards. Different scenarios that compared the costs of using conventional or reclaimed water in terms of water price and nutrient content were also studied. The results show that a proper combination of filters and emitters can save up to 33% in irrigation costs. Capital costs and maintenance costs were the most variable among the different combinations. Scenario analysis showed that the greater price of reclaimed water could be compensated by high nutrient contents, which would reduce fertilizer costs, El coste de la reutilización de agua en sistemas de riego por goteo a nivel de parcela no se ha estudiado en profundidad aunque la utilización de aguas residuales en agricultura es una alternativa viable en áreas con escasos recursos hídricos o con fuerte competencia por su uso. El objetivo del presente trabajo ha sido analizar los costes privados del uso del agua regenerada del riego por goteo en una parcela experimental. Se pretende que este análisis aporte información sobre cual sería la elección del regante según un criterio de costes si pudiera optar entre utilizar agua convencional o regenerada. Para ello, se analizaron los distintos componentes de los costes totales de diferentes combinaciones de cuatro tipos de filtros y cinco emisores comerciales, partiendo de los datos obtenidos en una parcela experimental en condiciones similares a las de una plantación de frutales. Se estudiaron también distintos escenarios en los que se comparaban los costes del uso de agua convencional o regenerada en función del precio de la misma y del contenido en nutrientes. Los resultados obtenidos indican que una correcta combinación de filtro y emisor puede ahorrar hasta un 33% de los costes de riego. Los costes de inversión y los de mantenimiento fueron los que más variaron entre las distintas combinaciones. El análisis de escenarios evidenció que el mayor precio del agua regenerada podría compensarse con una aportación elevada de nutrientes por parte de la misma, lo que permitiría reducir los costes de fertilización
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High-Performance-Tensile-Strength Alpha-Grass Reinforced Starch-Based Fully Biodegradable Composites

  • Gironès i Molera, Jordi
  • Espinach Orús, Xavier
  • Pellicer Johera, Neus
  • Tresserras Picas, Josep
  • Alcalà Vilavella, Manel
  • Mutjé Pujol, Pere
Though there has been a great deal of work concerning the development of natural fibers in reinforced starch-based composites, there is still more to be done. In general, cellulose fibers have lower strength than glass fibers; however, their specific strength is not far from that of fiberglass. In this work, alpha-fibers were obtained from alpha-grass through a mild cooking process. The fibers were used to reinforce a starch-based biopolymer. Composites including 5 to 35% (w/w) alpha-grass fibers in their formulation were prepared, tested, and subsequently compared with those of wood- and fiberglass-reinforced polypropylene (PP). The term “high-performance” refers to the tensile strength of the studied composites and is mainly due to a good interphase, a good dispersion of the fibers inside the matrix, and a good aspect ratio. The tensile strength of the composites showed a linear evolution for fiber contents up to 35% (w/w). The strain at break of the composites decreased with the fiber content and showed the stiffening effects of the reinforcement. The prepared composites showed high mechanical properties, even approaching those of glass fiber reinforced composites
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Tsallis Entropy for Geometry Simplification

  • Castelló, Pascual
  • González, Carlos
  • Chover, Miguel
  • Sbert, Mateu
  • Feixas Feixas, Miquel
This paper presents a study and a comparison of the use of different information-theoretic measures for polygonal mesh simplification. Generalized measures from Information Theory such as Havrda–Charvát–Tsallis entropy and mutual information have been applied. These measures have been used in the error metric of a surface simplification algorithm. We demonstrate that these measures are useful for simplifying three-dimensional polygonal meshes. We have also compared these metrics with the error metrics used in a geometry-based method and in an image-driven method. Quantitative results are presented in the comparison using the root-mean-square error (RMSE), This work was supported by the Spanish Ministry of Science and Innovation (Project TIN2010-21089-C03-03 and TIN2010-21089-C03-01) and Feder Funds, Bancaixa (Project P1.1B2010-08), Generalitat Valenciana (Project PROMETEO/2010/028) and Project 2009-SGR-643 of Generalitat de Catalunya (Catalan Government)
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¿Pueden contribuir los métodos visuales a avanzar hacia una investigación inclusiva? Un estudio sobre inclusión sociolaboral con personas con Trastorno Mental Grave (TMG) = Can visual methods help to go forward inclusive research? A study about social and labor inclusion with people with Severe Mental Illness (SMI)

  • Vilà Suñé, Montserrat
  • Fullana Noell, Judit
  • Pallisera, Maria
En este artículo se pretende mostrar cómo la utilización de métodos visuales en la investigación contribuye a potenciar la participación activa de las personas con TMG. Se utiliza como ejemplo un estudio de caso de corte cualitativo que incorpora tres actividades de componente visual (el dibujo “el río de la vida”, las fotografías y el dibujo de proyección de futuro) para favorecer la reflexión narrada que, sobre sus experiencias y vivencias, desarrollan cinco personas con TMG. El uso de las fotografías y dibujos en este estudio permite afirmar que estas estrategias se han mostrado válidas para acceder, en la medida que los participantes han querido, a esferas de vida personales en trayectorias vitales determinadas por la enfermedad mental, This article aims to show how the use of visual methods in research contributes to enhance the active participation of people with SMI, using as example a case study conducted. It’s a qualitative study which incorporates three visual activities (drawing "the river of life", photographs and drawing about the future) to encourage reflection on the life of five participants. Specifically, this paper presents the analysis of an example of each of these visual activities. The use of photographs and drawings in this study allows us to state that these strategies are very useful to better understand the personal life and pathways determined by mental illness
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Transición a la vida adulta de jóvenes con discapacidad intelectual. La opinión de los profesionales de servicios escolares y postescolares = Transition to adulthood of young people with intellectual disabilities. Views of professionals from school and postschool services

  • Pallisera, Maria
  • Fullana Noell, Judit
  • Martín Pazos, Raquel
  • Vilà Suñé, Montserrat
La transición a la edad adulta y vida activa es un proceso extremadamente complejo para los jóvenes con discapacidad. Para plantear propuestas de actuación que mejoren sus oportunidades de conseguir objetivos relacionados con la inclusión laboral y social en la vida adulta es imprescindible el diagnóstico en profundidad del contexto en que se construyen y desarrollan los procesos de transición. En este artículo se presenta un estudio en el que se ha aplicado el método Delphi con el propósito de obtener datos sobre la adecuación de los servicios o dispositivos que trabajan con jóvenes con discapacidad a lo largo de su proceso de transición a la edad adulta y vida activa, tanto en el escenario escolar como en el postescolar. Se han constituido dos paneles de expertos, uno con profesionales del ámbito educativo y otro con profesionales que trabajan en servicios postescolares. En ambos casos, los ejes temáticos son: visión del proceso de transición, aspectos curriculares y organizativos de los servicios, existencia de itinerarios de apoyo sistematizados, trabajo colaborativo entre profesionales, acciones de orientación con familias, adecuación de las alternativas postescolares, la formación de los profesionales, y coordinación de servicios. El análisis de los cuestionarios permite constatar las principales dificultades percibidas por los expertos en cada uno de los ámbitos y establece líneas básicas de actuación para mejorar los procesos de tránsito, entre las cuales destaca la necesidad de reforzar el papel de los equipos multiprofesionales en la articulación de redes de trabajo interprofesional, The transition to adulthood and working life is an extremely complex process for youth with disabilities. The diagnosis of the context in which young people with intellectual disabilities develop their transition to adult life is essential to make proposals that improve social and work inclusion. This article presents a study in which Delphi method has been applied in order to obtain data on the adequacy of the services that work with young people with disabilities throughout their transition to adulthood and active life. Two panels of experts, the first one with educational professionals and the second one professionals working with afterschool services, were asked about the following topics: vision of the transition process, curricular and organizational aspects of the services, support itineraries, collaboration between professionals, family counseling, adequacy of post-school options, professional training, and service coordination. The analysis of the questionnaires allowed us to identify the main barriers perceived by experts in each of the topics and to provide basic guidelines for improving transition processes. The need for reinforcing the role of multidisciplinary teams and enhancing interdisciplinary work are some of the findings of this research
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La Inclusión laboral de los jóvenes con discapacidad intelectual: un reto para la orientación psicopedagógica = Labour market inclusion for young people with learning difficulties: a challenge for psycho-educational guidance

  • Vilà Suñé, Montserrat
  • Pallisera, Maria
  • Fullana Noell, Judit
Para favorecer la inclusión laboral de los jóvenes con discapacidad intelectual es necesario analizar los procesos formativos y los procesos de orientación psicopedagógica que se producen especialmente en la educación secundaria. En este trabajo, y fruto de nuestra línea de investigación más reciente, planteamos distintas estrategias que, desde el ámbito de la orientación psicopedagógica, deben promoverse en la educación secundaria si se quiere asegurar un proceso inclusivo en el tránsito a la vida laboral de los alumnos con discapacidad intelectual: la implicación de la administración educativa en la definición de un marco legal que establezca claramente la responsabilidad de la escuela secundaria en estos procesos, un modelo de orientación educativa y sociolaboral que se integre en las distintas áreas del currículum de secundaria y sea tenido en cuenta en la acción tutorial; así como el equilibrio de los currícula académicos con componentes relacionados con las habilidades sociales y la autodeterminación. Ifinalmente, se presenta la Planificación Centrada en la Persona (PCP) como un enfoque innovador que aporta nuevas perspectivas en el apoyo a los itinerarios socioeducativos y laborales de las personas con discapacidad intelectual, en la medida que éstos se articulan necesariamente como respuesta a proyectos de vida deseados, singulares y únicos
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Measurement of the specific heat and determination of the thermodynamic functions of relaxed amorphous silicon

  • Roura Grabulosa, Pere
  • Taïr, Fadila
  • Farjas Silva, Jordi
  • Roca i Cabarrocas, Pere
The specific heat, cp, of two amorphous silicon (a-Si) samples has been measured by differential scanning calorimetry in the 100–900K temperature range. When the hydrogen content is reduced by thermal annealing, cp approaches the value of crystalline Si (c-Si). Within experimental accuracy, we conclude that cp of relaxed pure a-Si coincides with that of c-Si. This result is used to determine the enthalpy, entropy, and Gibbs free energy of defect-free relaxed a-Si. Finally, the contribution of structural defects on these quantities is calculated and the melting point of several states of a-Si is predicted
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