Articles publicats (D-EMCI)http://hdl.handle.net/10256/71432017-05-23T14:04:30Z2017-05-23T14:04:30ZFirst proof of topological signature in the high pressure xenon gas TPC with electroluminescence amplification for the NEXT experimentFerrario, P.Laing, A.López-March, N.Gómez-Cadenas, J. J.Álvarez, V.Azevedo, C. D RBorges, F. I GCárcel, S.Cebrián, S.Cervera, A.Conde, C. A NDafni, T.Díaz, J.Diesburg, M.Esteve, R.Fernandes, L. M PFerreira, A. L.Freitas, E. D CGehman, V. M.Goldschmidt, A.González-Díaz, D.Gutiérrez, R. M.Hauptman, J.Henriques, C. A OHernando Morata, J. A.Irastorza, I. G.Labarga, L.Lebrun, P.Liubarsky, I.Lorca, D.Losada, M.Luzón, G.Marí, A.Martín-Albo, J.Martínez-Lema, G.Martínez, A.Miller, T.Monrabal, F.Monserrate, M.Monteiro, C. M.B.Mora, F. J.Moutinho, L. M.Muñoz Vidal, J.Nebot-Guinot, M.Novella, P.Nygren, D.Para, A.Pérez, J.Pérez Aparicio, J. L.Querol, M.Renner, J.Ripoll, L.Rodríguez, J.Santos, F. P.dos Santos, J. M FSerra, L.Shuman, D.Simón, A.Sofka, C.Sorel, M.Toledo, J. F.Torrent, J.Tsamalaidze, Z.Veloso, J. F C AVillar, J. A.Webb, R.White, J. T.Yahlali, N.Yepes-Ramírez, H.http://hdl.handle.net/10256/139852017-05-23T13:27:14Z2016-01-19T00:00:00ZFirst proof of topological signature in the high pressure xenon gas TPC with electroluminescence amplification for the NEXT experiment
Ferrario, P.; Laing, A.; López-March, N.; Gómez-Cadenas, J. J.; Álvarez, V.; Azevedo, C. D R; Borges, F. I G; Cárcel, S.; Cebrián, S.; Cervera, A.; Conde, C. A N; Dafni, T.; Díaz, J.; Diesburg, M.; Esteve, R.; Fernandes, L. M P; Ferreira, A. L.; Freitas, E. D C; Gehman, V. M.; Goldschmidt, A.; González-Díaz, D.; Gutiérrez, R. M.; Hauptman, J.; Henriques, C. A O; Hernando Morata, J. A.; Irastorza, I. G.; Labarga, L.; Lebrun, P.; Liubarsky, I.; Lorca, D.; Losada, M.; Luzón, G.; Marí, A.; Martín-Albo, J.; Martínez-Lema, G.; Martínez, A.; Miller, T.; Monrabal, F.; Monserrate, M.; Monteiro, C. M.B.; Mora, F. J.; Moutinho, L. M.; Muñoz Vidal, J.; Nebot-Guinot, M.; Novella, P.; Nygren, D.; Para, A.; Pérez, J.; Pérez Aparicio, J. L.; Querol, M.; Renner, J.; Ripoll, L.; Rodríguez, J.; Santos, F. P.; dos Santos, J. M F; Serra, L.; Shuman, D.; Simón, A.; Sofka, C.; Sorel, M.; Toledo, J. F.; Torrent, J.; Tsamalaidze, Z.; Veloso, J. F C A; Villar, J. A.; Webb, R.; White, J. T.; Yahlali, N.; Yepes-Ramírez, H.
The NEXT experiment aims to observe the neutrinoless double beta decay of 136Xe in a high-pressure xenon gas TPC using electroluminescence (EL) to amplify the signal from ionization. One of the main advantages of this technology is the possibility to reconstruct the topology of events with energies close to Qββ. This paper presents the first demonstration that the topology provides extra handles to reject background events using data obtained with the NEXT-DEMO prototype. Single electrons resulting from the interactions of 22Na 1275 keV gammas and electronpositron pairs produced by conversions of gammas from the 228Th decay chain were used to represent the background and the signal in a double beta decay. These data were used to develop algorithms for the reconstruction of tracks and the identification of the energy deposited at the end-points, providing an extra background rejection factor of 24.3 ± 1.4 (stat.)%, while maintaining an efficiency of 66.7 ± 1.% for signal events
2016-01-19T00:00:00ZSensitivity of NEXT-100 to neutrinoless double beta decayMartín Albo, J.Muñoz Vidal, J.Ferrario, P.Nebot Guinot, M.Gómez Cadenas, J. J.Álvarez, V.Azevedo, C. D.R.Borges, F. I.G.Cárcel, S.Carrión, J. V.Cebrián, S.Cervera, A.Conde, C. A.N.Díaz, J.Diesburg, M.Esteve, R.Fernandes, L. M.P.Ferreira, A. L.Freitas, E. D.C.Goldschmidt, A.González Díaz, D.Gutiérrez, R. M.Hauptman, J.Henriques, C. A.O.Hernando Morata, J. A.Herrero, V.Labarga, L.Laing, A.Lebrun, P.Liubarsky, I.López March, N.Lorca, D.Losada, M.Martínez Lema, G.Martínez, A.Monrabal, F.Monteiro, C. M.B.Mora, F. J.Moutinho, L. M.Novella, P.Nygren, D.Palmeiro, B.Para, A.Querol, M.Renner, J.Ripoll Masferrer, LluísRodríguez, J.Santos, F. P.dos Santos, J. M.F.Serra, L.Shuman, D.Simón, A.Sofka, C.Sorel, M.Stiegler, T.Toledo, J. F.Torrent, J.Tsamalaidze, Z.Veloso, J. F.C.A.Webb, R.White, J. T.Yahlali, N.Yepes Ramírez, H.http://hdl.handle.net/10256/139842017-05-17T00:00:59Z2016-05-26T00:00:00ZSensitivity of NEXT-100 to neutrinoless double beta decay
Martín Albo, J.; Muñoz Vidal, J.; Ferrario, P.; Nebot Guinot, M.; Gómez Cadenas, J. J.; Álvarez, V.; Azevedo, C. D.R.; Borges, F. I.G.; Cárcel, S.; Carrión, J. V.; Cebrián, S.; Cervera, A.; Conde, C. A.N.; Díaz, J.; Diesburg, M.; Esteve, R.; Fernandes, L. M.P.; Ferreira, A. L.; Freitas, E. D.C.; Goldschmidt, A.; González Díaz, D.; Gutiérrez, R. M.; Hauptman, J.; Henriques, C. A.O.; Hernando Morata, J. A.; Herrero, V.; Labarga, L.; Laing, A.; Lebrun, P.; Liubarsky, I.; López March, N.; Lorca, D.; Losada, M.; Martínez Lema, G.; Martínez, A.; Monrabal, F.; Monteiro, C. M.B.; Mora, F. J.; Moutinho, L. M.; Novella, P.; Nygren, D.; Palmeiro, B.; Para, A.; Querol, M.; Renner, J.; Ripoll Masferrer, Lluís; Rodríguez, J.; Santos, F. P.; dos Santos, J. M.F.; Serra, L.; Shuman, D.; Simón, A.; Sofka, C.; Sorel, M.; Stiegler, T.; Toledo, J. F.; Torrent, J.; Tsamalaidze, Z.; Veloso, J. F.C.A.; Webb, R.; White, J. T.; Yahlali, N.; Yepes Ramírez, H.
NEXT-100 is an electroluminescent high-pressure xenon gas time projection chamber that will search for the neutrinoless double beta (0νββ) decay of 136Xe. The detector possesses two features of great value for 0νββ searches: energy resolution better than 1% FWHM at the Q value of 136Xe and track reconstruction for the discrimination of signal and background events. This combination results in excellent sensitivity, as discussed in this paper. Material-screening measurements and a detailed Monte Carlo detector simulation predict a background rate for NEXT-100 of at most 4 × 10−4 counts keV−1 kg−1 yr−1. Accordingly, the detector will reach a sensitivity to the 0νββ-decay half-life of 2.8 × 1025 years (90% CL) for an exposure of 100 kg·year, or 6.0 × 1025 years after a run of 3 effective years
2016-05-26T00:00:00ZOptimization of composite stiffened panels under mechanical and hygrothermal loads using neural networks and genetic algorithmsMarín Hernández, LorenaTrias Mansilla, DanielBadalló i Cañellas, PereMayugo Majó, Joan Andreuhttp://hdl.handle.net/10256/137822017-03-28T00:00:55Z2012-11-01T00:00:00ZOptimization of composite stiffened panels under mechanical and hygrothermal loads using neural networks and genetic algorithms
Marín Hernández, Lorena; Trias Mansilla, Daniel; Badalló i Cañellas, Pere; Mayugo Majó, Joan Andreu
The present work develops an optimization procedure for a geometric design of a composite material stiffened panel with conventional stacking sequence using static analysis and hygrothermal effects. The procedure is based on a global approach strategy, composed by two steps: first, the response of the panel is obtained by a neural network system using the results of finite element analyses and, in a second step, a multi-objective optimization problem is solved using a genetic algorithm. The neural network implemented in the first step uses a sub-problem approach which allows to consider different temperature ranges. The compression load and relative humidity of the air are assumed to be constants throughout the considered temperature range.The mass, the hygrothermal expansion and the stresses between the skin and the stiffeners are defined as the optimality criteria. The presented optimization procedure is shown to yield the optimal structure design without compromising the computational efficiency
2012-11-01T00:00:00ZA simulation method for high-cycle fatigue-driven delamination using a cohesive zone modelBak, Brian L VTuron Blasco, AlbertLindgaard, EsbenLund, Erikhttp://hdl.handle.net/10256/137332017-03-15T01:00:57Z2016-04-20T00:00:00ZA simulation method for high-cycle fatigue-driven delamination using a cohesive zone model
Bak, Brian L V; Turon Blasco, Albert; Lindgaard, Esben; Lund, Erik
A novel computational method for simulating fatigue-driven mixed-mode delamination cracks in laminated structures under cyclic loading is presented. The proposed fatigue method is based on linking a cohesive zone model for quasi-static crack growth and a Paris' law-like model described as a function of the energy release rate for the crack growth rate during cyclic loading. The J-integral has been applied to determine the energy release rate. Unlike other cohesive fatigue methods, the proposed method depends only on quasi-static properties and Paris' law parameters without relying on parameter fitting of any kind. The method has been implemented as a zero-thickness eight-node interface element for Abaqus and as a spring element for a simple finite element model in MATLAB. The method has been validated in simulations of mode I, mode II, and mixed-mode crack loading for both self-similar and non-self-similar crack propagation. The method produces highly accurate results compared with currently available methods and is capable of simulating general mixed-mode non-self-similar crack growth problems
2016-04-20T00:00:00ZInternal geometric modelling of 3D woven composites: A comparison between different approachesIsart Valle, NativitatEl Said, B.Ivanov, D.S.Hallett, S.R.Mayugo Majó, Joan AndreuBlanco Villaverde, Norberthttp://hdl.handle.net/10256/137322017-03-15T01:00:55Z2015-11-15T00:00:00ZInternal geometric modelling of 3D woven composites: A comparison between different approaches
Isart Valle, Nativitat; El Said, B.; Ivanov, D.S.; Hallett, S.R.; Mayugo Majó, Joan Andreu; Blanco Villaverde, Norbert
The mechanical behaviour of 3D woven composite materials is affected by deformations as resulting from the manufacturing process. The present study is based on comparison of three different methodologies to predict the internal yarn geometries of 3D through-thickness orthogonal interlock. The first approach idealises the geometry, which is obtained directly from manufacturing parameters assuming constant elliptical cross-sections. The second technique generates the yarn geometry from the Digital Element Method, which simulates the compaction process of the material. The last method considered is an analytical method defining longitudinal and transverse contours, which describe the undulation of fill, warp and binder yarns. The yarn geometries from the different methods are numerically analysed using voxel finite element analysis to determine the global volume fraction and the elastic properties. The results are also compared with experimental values to determine the strengths and weaknesses of each approach. The first approach is quicker than the others although the geometry is not the most accurate. The second and third method have a good match between the predicted geometry and optical micrograph of the fabric and the elastic properties are very similar for both methods
2015-11-15T00:00:00ZAn experimental data reduction method for the Mixed Mode Bending test based on the J-integral approachSarrado Molina, CarlosTuron Travesa, AlbertRenart Canalias, JordiCosta i Balanzat, Josephttp://hdl.handle.net/10256/137312017-03-15T01:00:58Z2015-09-29T00:00:00ZAn experimental data reduction method for the Mixed Mode Bending test based on the J-integral approach
Sarrado Molina, Carlos; Turon Travesa, Albert; Renart Canalias, Jordi; Costa i Balanzat, Josep
The Mixed Mode Bending test (MMB) is suitable for measuring the interlaminar fracture toughness of composite materials under mixed-mode loading. Data reduction is usually based on the assumptions of Linear Elastic Fracture Mechanics, which are not fulfilled in configurations involving large scale fracture, such as in adhesive joints. In this work, a J-integral-based method that can be applied in presence of large fracture process zones is presented. The proposed method requires less input information and avoids crack length monitoring during the test, which reduces the uncertainty of the results as compared to traditional methods. The method is shown to accurately compute the fracture toughness in a delamination test campaign and to provide results with lower uncertainty than those of the ASTM standard method
2015-09-29T00:00:00ZNew method for medical devices design and manufacture: Case study-scapholunate implantFerrer Mallorquí, InèsGrabalosa Saubí, JordiSalvador, AntoniElías-Zúñiga, AlexCiurana, Quim dehttp://hdl.handle.net/10256/137232017-03-10T01:01:10Z2016-10-01T00:00:00ZNew method for medical devices design and manufacture: Case study-scapholunate implant
Ferrer Mallorquí, Inès; Grabalosa Saubí, Jordi; Salvador, Antoni; Elías-Zúñiga, Alex; Ciurana, Quim de
The scapholunate interosseous ligament is located between the scaphoid and lunate bones and if it torns causes instability, leading to weakness in the hand, chronic pain, and lack of motion. While many treatment options are available, based on the type of instability, all of them present side effects including stiffness in the wrist, long recovery times, and widespread scarring. As such, wrist prostheses have been introduced as an alternative treatment. As suitable scapholunate prostheses implanted using arthroscopy are a promising option in reducing complications associated with conservative treatments, this work proposes a new implant designed to replace the scapholunate ligament. The implant is a completely new design, which was manufactured to determine its workability. Medical experts and engineers approved and validated the new design process, and the prototype obtained will be used to evaluate performance and to propose possible future improvements
2016-10-01T00:00:00ZPolymer incremental sheet forming process: Temperature analysis using response surface methodologyGarcia-Romeu, M. L.Bagudanch Frigolé, IsabelVives Mestres, MarinaSabater Armengou, Marchttp://hdl.handle.net/10256/137222017-03-10T01:00:56Z2017-01-02T00:00:00ZPolymer incremental sheet forming process: Temperature analysis using response surface methodology
Garcia-Romeu, M. L.; Bagudanch Frigolé, Isabel; Vives Mestres, Marina; Sabater Armengou, Marc
To reduce costs associated with the manufacturing of customized products, several innovative forming processes have been developed. Incremental sheet forming (ISF) is one of these new technologies, becoming, in the past decade, more interesting for the academic and industrial community. The influence of main process parameters, namely, tool diameter, spindle speed, feed rate, and step down, is studied in depth in this paper. The maximum temperature achieved during the forming process of a truncated pyramid frustum with a circular generatrix using three nonbiocompatible and two biocompatible polymer materials is measured. Box–Behnken design of experiments and the response surface methodology have been utilized to statistically analyze the results and to provide models able to predict the maximum temperatures
2017-01-02T00:00:00ZEffects of the underdrain design on the pressure drop in sand filtersPujol i Sagaró, ToniArbat Pujolràs, GerardBové Masmiquel, JosepPuig Bargués, JaumeDuran i Ros, MiquelVelayos Solé, JoaquimRamírez de Cartagena Bisbe, Franciscohttp://hdl.handle.net/10256/136862017-03-02T01:01:02Z2016-10-01T00:00:00ZEffects of the underdrain design on the pressure drop in sand filters
Pujol i Sagaró, Toni; Arbat Pujolràs, Gerard; Bové Masmiquel, Josep; Puig Bargués, Jaume; Duran i Ros, Miquel; Velayos Solé, Joaquim; Ramírez de Cartagena Bisbe, Francisco
The effect of the nozzle geometry on the pressure drop of a sand filter was experimentally studied. Four nozzles were analysed: one commercially produced with a conical shape and three alternative cylindrical underdrains that differed in the location and the number of slots. Experiments in both filtration mode and backwashing conditions for a wide range of superficial velocities were carried out. The results reported a reduction of the filter energy consumption greater than 20% could be achieved by simply modifying the position of the slots above the surface of the underdrain element. The effects of the nozzle were further investigated by means of an analytical model that correctly predicted the pressure drop of the water flow through the filter. The model confirmed that the distribution of the slots in the underdrain was a critical factor for determining the length of the region with a non-uniform flow within the sand. When using the commercial nozzle at flow rates >0.85 l s−1, this region produced the major contribution to energy losses in the filter due to increases in the tortuosity of the water path within the porous medium. From these results, it is suggested that an affordable way to increase the energy efficiency of already existing installations would be to replace the current underdrain elements with new improved designs
2016-10-01T00:00:00ZExperimental study of the influence of adhesive properties and bond length on the bond behaviour of NSM FRP bars in concreteBarris Peña, CristinaBaena Muñoz, MartaTorres Llinàs, LluísSharaky, Ibrahim Attiahttp://hdl.handle.net/10256/136752017-03-01T01:01:05Z2016-08-17T00:00:00ZExperimental study of the influence of adhesive properties and bond length on the bond behaviour of NSM FRP bars in concrete
Barris Peña, Cristina; Baena Muñoz, Marta; Torres Llinàs, Lluís; Sharaky, Ibrahim Attia
The near-surface mounted (NSM) fibre reinforced polymer (FRP) technique is a relatively recent system for strengthening concrete structures. Bond is a key factor in its behaviour, and is affected by many factors whose influence can only be tested through experimental studies. In this study, the modified pull-out test was used to study the effect of epoxy properties and bond length on the behaviour of NSM FRP bars. Three epoxy types, two FRP materials (carbon and glass) and four bond lengths (6db, 12db, 24db and 30db) are used. The load capacity, slips at the loaded end and free end and average bond stress are all analysed. The test results indicate that the role of epoxy properties appear to be a key factor in bond performance in the NSM FRP strengthening technique, and that their effect varies depending on bond length and FRP properties
2016-08-17T00:00:00Z