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Comparative Study of Multivariate Methods to Identify Paper Finishes Using Infrared Spectroscopy

  • Riba Ruiz, Jordi-Roger
  • Canals Parelló, Trini
  • Cantero Gómez, María Rosa
Recycled paper is extensively used worldwide. In the last decades its market has expanded considerably. The increasing use of recycled paper in papermaking has led to the production of paper containing several types of impurities. Consequently, wastepaper mills are forced to implement quality control schemes for evaluating the incoming wastepaper stock, thus guarantying the specifications of the final product. The main objective of this work is to present a fast and reliable system for identifying different paper types. Therefore, undesirable paper types can be refused, improving the performance of the paper machine and the final quality of the paper manufactured. For this purpose two fast techniques, i.e., Fourier transform mid-infrared (FTIR) and reflectance near-infrared (*IR) were applied to acquire the infrared spectra of the paper samples. *ext, four processing multivariate methods, i.e., principal component analysis (PCA), canonical variate analysis (CVA), extended canonical variate analysis (ECVA) and support vector machines (SVM) were employed in the feature extraction –or dimension reduction– stage. Afterwards, the k nearest neighbors algorithm (k**) was used in the classification phase. Experimental results show the usefulness of the proposed methodology and the potential of both FTIR and *IR spectroscopic methods. Using the FTIR spectrum in association with SVM and k** the system achieved maximum classification accuracy of 100%, whereas using the *IR spectrum in association with ECVA or SVM and k** the system achieved maximum classification accuracy of 96.4%
Proyecto:


Design Through Play: The Archispiel Experience, El juego como metodología del proyecto. La experiencia Archispiel

  • Elvira Peña, Juan
  • Paez, Roger
Este artículo estudia las implicaciones y potencialidades de las prácticas lúdicas y los formatos de juego, entendidos como herramientas docentes innovadoras en arquitectura, urbanismo y, en general, el diseño. Hace una breve introducción a los pioneros de los juegos serios y el estado del arte en lo que diversos autores denominan 'el juego como metodología de diseño". A continuación, presenta Archispiel, un formato de proyecto que emplea el juego como metodología fundamental. Diseñado por los autores en 2015, fue empleado por primera vez en el contexto docente en el taller Magaluf Reset. Basado en juegos de estrategia y juegos de guerra tradicionales diseñados a partir de los años 50 del siglo pasado, combina la negociación estratégica con el uso del azar para producir efectos inesperados en el transcurso del juego. Por lo tanto, más que proporcionar respuestas a un estado de la cuestión previamente establecido, sus resultados son de manera literal el resultado de una lógica de diseño especulativa y abierta. La experiencia descrita muestra el modo en que el diseño fundamentado en el juego ofrece una amplia gama de posibilidades de exploración fuera de las posibilidades de las prácticas de proyecto tradicionales., This paper focuses on the implications and potentialities of playful practices and game formats as innovative teaching methods in architecture, urban planning and, more generally, design. It provides a very brief account of serious games pioneers and the current state of the art of what the authors call ‘design through play’. It then presents one game-based format, Archispiel, designed by the authors in 2015, along with a case study of its use in a classroom context, Magaluf Reset. The exercise, drawing on traditional war games and diplomacy games designed from the 1950s onwards, combines strategic negotiation with the use of chance to produce unexpected effects. Consequently, rather than solutions answering to a predefined brief, the results are quite literally the outcome of an exploratory and open-ended design logic. The experience shows how design through play offers a rich array of explorative possibilities not afforded by conventional design practices., Peer Reviewed
Proyecto:


Modelo numérico del comportamiento histerético de uniones entre forjados reticulares y pilares de fachada, Numerical model of the hysteretic behavior of connections between waffle slabs and façade supports

  • Cahís, X.
  • Benavent-Climent, A.
  • Catalán Goñi, A.
Las estructuras de forjados reticulares sobre pilares aislados han sido ampliamente utilizadas en el sur de Europa para edificios de viviendas y oficinas entre los años setenta y noventa del siglo pasado. Estas estructuras, proyectadas y construidas con códigos actualmente obsoletos, podrían tener un comportamiento deficiente en caso de terremoto y es necesario evaluar su vulnerabilidad y la necesidad de ser reacondicionadas sísmicamente. Este artículo propone un modelo sencillo de transmisión de esfuerzos en uniones existentes entre forjado reticular y soporte exterior, solicitadas en la dirección normal al plano de fachada. La propuesta tiene en cuenta particularidades de estos forjados tales como la concentración de armaduras orientadas con los nervios y la presencia sistemática de crucetas de punzonamiento. El modelo global consiste en elementos tipo barra para los soportes y tipo placa para el forjado, con uniones entre ambos mediante rótulas a flexión y a torsión. La resistencia de las rótulas a flexión se determina a partir de la estimación de la porción de armadura longitudinal del forjado que transmite directamente momentos al pilar por flexión. La deformación de plastificación de las rótulas se estima con expresiones simples. Como ductilidad de las rótulas a flexión se adopta el valor propuesto por la norma FEMA 356, mientras que para las rótulas a torsión se adopta ductilidad infinita, lo cual es consistente con resultados experimentales previos. Se muestra que la respuesta frente a desplazamientos laterales impuestos monótonamente crecientes obtenida con el modelo propuesto se ajusta adecuadamente a resultados experimentales obtenidos en estudios anteriores, en cuanto a rigidez, resistencia y ductilidad., Waffle-flat-plate structures have been widely used for residential and office buildings in the South of Europe between the seventies and nineties of the last century. These buildings were designed with old seismic codes and its vulnerability needs to be evaluated to determine whether they need to be seismic retrofitted or not. This article proposes a simple model that represents the moment transfer between plate and column, for existing exterior connections loaded in the direction normal to the building façade. The model takes into account singularities of existing waffle-flat-plate structures such as the concentration of reinforcement in the direction of the joints, and the existence of punching shear reinforcement. The model consists of frame elements for the columns and shell elements for the slabs, both connected with flexural and torsion hinges. The strength of the flexural hinges is obtained by estimating the portion of longitudinal reinforcement of the plate that transfers directly the unbalanced moment to the column by flexure. The yielding deformations of the flexural and torsion hinges are estimated with simple expressions. The ductility of the flexural hinges is taken from FEMA 356, while infinite ductility is adopted for the torsional hinges in accordance with previous experimental studies. It is shown that the proposed model provides a good approximation of the experimental response of the connection under monotonically increasing lateral displacements, in terms of stiffness, strength and ductility., Peer Reviewed
Proyecto:


The effect of gravity in transient fluid-structure interaction simulations of a large wind turbine with composite blades

  • Santo, G.
  • Peeters, M.
  • Van Paepegem, W.
  • Degroote, J.
In this work the effect of the gravity force on the fluid-structure interaction (FSI) simulation of a large horizontal axis wind turbine (HAWT) is analyzed in detail. FSI simulations with and without gravity are carried out and compared in order to highlight the effect of gravity force on the loads and performance of the analyzed HAWT.
Proyecto:


Recent developments of SPH in modeling explosion and impact problems

  • Liu, M.B.
  • Feng, D.I.
  • Guo, Z.M.
Explosion and impact problems are generally characterized by the presence of shock waves, intense localized materials response and intensive loadings. Most of the wave propagation hydro-codes for such problems use traditional grid based methods such as finite difference methods (FDM) and finite element methods (FEM). Though many successful achievements have been made using these methods, some numerical difficulties still exist. These numerical difficulties generally arise from large deformations, large inhomogeneities, and moving interfaces, free or movable boundaries. Smoothed particle hydrodynamics (SPH) is a Lagrangian, meshfree particle method, and has been widely applied to different areas in engineering and science. SPH method has been intensively used for simulating high strain hydrodynamics with material strength, due to its special features of meshfree, Lagrangian and particle nature. In this paper, some recent developments of the SPH in modelling explosion and impact problems will be introduced. A modified scheme for approximating kernel gradient (kernel gradient correction, or KGC) has been used in the SPH simulation to achieve better accuracy and stability. The modified SPH method is used to simulate a number of problems including 1D TNT detonation, linear shaped charge and explosively driven welding. The effectiveness of the modified SPH method has been demonstrated by comparative studies of the SPH results with data from other resources.
Proyecto:


Diseño de un triciclo eléctrico para el reparto de mercancías

  • Cárdenas Fernández, Alex
El proyecto consiste en el desarrollo conceptual y detallado de una bicicleta eléctrica, preferentmente con baterias. El proyecto partirá de la investigación y desarrollo del sistema completo, y posteriormente intensificará su trabajo en uno de los subsistemas principales (como ahora la tracción, control, baterias, BMS, etc.).
Proyecto:


Migration of a generic multi-physics framework to HPC environments

  • Dadvand, Pooyan
  • Rossi, Riccardo
  • Gil, Marisa
  • Martorell Bofill, Xavier
  • Cotela Dalmau, Jordi
  • Juanpere, E.
  • Idelsohn Barg, Sergio Rodolfo
  • Oñate Ibáñez de Navarra, Eugenio
Creating a highly parallelizable code is a challenge specially for distributed memory machines (DMMs). Moreover, algorithms and data structures suitable for these platforms can be very different from the ones used in serial code. For this reason, many programmers in the field prefer to start their own code from scratch. However, for an already existing framework supported by a long-time expertise the idea of transformation becomes attractive in order to reuse the effort done during years of development. In this presentation we explain how a relatively complex framework but with modular structure can be prepared for high performance computing with minimum modification. Kratos Multi-Physics [1] is an open source generic multi-disciplinary platform for solution of coupled problems consist of fluid, structure, thermal and electromagnetic fields. The parallelization of this framework is performed with objective of enforcing the less possible changes to its different solver modules and encapsulate the changes as much as possible in its common kernel. This objective is achieved thanks to the Kratos design and also innovative way of dealing with data transfers for a multi-disciplinary code. This work is completed by the migration of the framework from the x86 architecture to the Marenostrum Supercomputing platform. The migration has been verified by a set of benchmarks which show high scalability, from which we present the Telescope problem in this paper.
Proyecto:


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