313 research outputs found
Reglage métier rectiligne et leur influence sur la longueur de fil par maille
La característica más singular de los tejidos de malla es su extensibilidad. Esta extensibilidad conlleva una deformación del tejido y, por tanto, un cambio de sus dimensiones originales. Las densidades y el peso dependerán del estado de tensión en que se mida el tejido, sin embargo, la longitud de malla es un parámetro estructural que permanece invariante sea cual sea el estado del tejido en crudo.
Este trabajo, analiza, en primer lugar, las diferencias entre varios métodos manuales para medir esta longitud y, después, se verifica la relación funcional entre las densidades del punto liso y la longitud de malla para unas determinadas condiciones industriales de trabajo.The most defining characteristic of knitted fabrics is their stretchability, which tends to cause deformations in the fabric and, consequently, changes in their dimensions. The densities and weight depend on the stress state of fabric ,however, the length absorbed by stitch (LAS) is a structural parameter which remains unaltered regardless of the state of the fabric (in its raw state)
Firstly, this work analyses the differences between various simple methods for determining this length. Secondly, the functional relationship between the densities of the plain structure and the LAS is analysed for given industrial working conditions.La caractéristique la plus singulière des tissus à mailles est leur extensibilité qui entraîne généralement une déformation du tissu et, par conséquent, des changements dans leurs dimensions. Les densités et le poids dépendront d l´état de tension du tissu ; toutefois, la longueur de fil absorbée par une maille est un para mètre structural qui demeure inaltéré quel que soit l´état dans lequel se trouve le tissu écru.
Ce travail analyse, en premier lieu, les différences entre plusieurs méthodes simples pour déterminer cette longueur et vérifier le rapport fonctionnel entre les densités du jersey et la longueur de fil par maille pour certaines conditions industrielles de travail
Estudi de les preferències dels alumnes en la gamificació
L'interès d'aquest treball prové del fet que el projecte de la unitat didàctica realitzada consisteix precisament en la creació d'un joc creat pels alumnes, mitjançant Scratch. Es parteix d'una situació en la qual es desconeixen les preferències de gamificació de l'alumnat, i a partir d'aquí es defineix una sèrie de processos (enquestes, formularis, entrevistes, etc.) mitjançant els quals s'obté informació d'aquestes preferències. Es preveu recopilar informació sobre la forma d'obtenció de dades i enquestes, la preparació d'aquestes, la realització de la consulta i la seva documentació. En aquest projecte els alumnes adquiriran competències dels continuts de l'àmbit Científic-tecnològic de Tecnologia de 2n de l'ESO (Blocs: Llenguatges de Programació, El procès tecnològic) utilitzant el llenguatge de programació Scratch. S'aplicaran metodologies de treball per projectes de manera cooperativa. L'entorn de scratch permet compartir les seves creacions, per tant els permet compartir informació i aprendre competències de manera conjunta. Un cop hagin realitzat el joc (del seu propi disseny i creació), el compartiran amb els companys, els provaran i s'avaluaran entre ells. Durant les primeres sessions s'ensenyarà el funcionament de la programació scratch i posteriorment es formaran els grups. Cada grup escollirà el tema i la dinàmica del joc i finalment es realitzarà el joc. En les últimes sessions es compartiran els projectes i es donaran retroacció entre ells
Influence de l'aiguille de coudre sur la pénétration de tissus "Denim"
Se estudia la fuerza de penetración en una serie de tejidos “denim” con el comprobador de costurabilidad L&M. Se estudia la influencia del número de capas, la dirección de costura, título de la aguja y forma de la punta. Se ha aplicado un diseño factorial mixto para cada uno de los tejidos analizados. A partir de los efectos principales y las interacciones se derivan las condiciones de cosido más favorables.The penetration force is studied in a series of weaves " denim " with the sewability tester L&M. It is studied the influence of the number of layers, the direction of the seam, size of the needle and form of the point. A mixed factorial design has been applied for each one of the analyzed fabrics. Starting from the main effects and the interactions are derived the conditions of sewing more favorable.La force de la pénétration est étudiée dans une série de tissus " denim" avec le vérificateur L&M tester. Il est étudié l'influence du nombre de couches, la direction de la couture, diamètre de l'aiguille et forme de la pointe. Un dessin factoriel mixte a été sollicité chacun des structures analysées. Après des effets principaux et les interactions est dérivé les conditions plus favorables pour les coutures utilisées sur les tissus
Effects of Sigma-1 Receptor Ligands on Peripheral Nerve Regeneration
Peripheral nerve injuries lead to the loss of motor, sensory and autonomic functions in the territories supplied by the injured nerve. Currently, nerve injuries are managed by surgical repair procedures, and there are no effective drugs in the clinic for improving the capacity of axonal regeneration. Sigma-1 receptor (Sig-1R) is an endoplasmic reticulum chaperon protein involved in many functions, including neuroprotection and neuroplasticity. A few previous studies using Sig-1R ligands reported results that suggest this receptor as a putative target to enhance regeneration. The aim of this study was to evaluate the possible effects of Sig-1R ligands on axonal regeneration in a sciatic nerve section and repair model in mice. To this end, mice were treated either with the Sig-1R agonist PRE-084 or the antagonist BD1063, and a Sig-1R knock-out (KO) mice group was also studied. The electrophysiological and histological data showed that treatment with Sig-1R ligands, or the lack of this protein, did not markedly modify the process of axonal regeneration and target reinnervation after sciatic nerve injury. Nevertheless, the nociceptive tests provided results indicating a role of Sig-1R in sensory perception after nerve injury, and immunohistochemical labeling indicated a regulatory role in inflammatory cell infiltration in the injured nerve
Investigating the capabilities of CFD-based data-driven models for indoor environmental design and control
In this work, we study the accuracy of CFD-based data-driven models, which predict comfort-related flow parameters in a ventilated cavity with a heated floor. We compare the computational cost and accuracy of three different models, namely artificial neural network, support vector regression, and gradient boosting regression. The tested scenarios include short and long cavities with different inlet velocities. Among the studied frameworks, the artificial neural network provides the most accurate predictions for most of the tested flow configurations. However, test configurations with jet separation and a secondary vortex are more difficult to predict correctly; thus more high-fidelity data is required in order to construct a more robust and reliable model.This work is supported by the Ministerio de Economía y Competitividad, Spain [ENE2017-88697-R]. N. Morozova is supported by the by the Ministerio de Economía y Competitividad, Spain [FPU16/06333 predoctoral contract]. Part of the calculations was performed on the MareNostrum 4 supercomputer at the Barcelona Supercomputing Center [RES project IM-2021-1-0015]. The authors thankfully acknowledge these institutions.Postprint (published version
Investigación textil en España: un caso de aplicación de indicadores bibliométricos a nivel micro
On the feasibility of affordable high-fidelity CFD simulations for indoor environment design and control
Computational fluid dynamics (CFD) is a reliable tool for indoor environmental applications. However, accurate CFD simulations require large computational resources, whereas significant cost reduction can lead to unreliable results. The high cost prevents CFD from becoming the primary tool for indoor environmental simulations. Nonetheless, the growth in computational power and advances in numerical algorithms provide an opportunity to use accurate and yet affordable CFD. The objective of this study is to analyze the feasibility of fast, affordable, and high-fidelity CFD simulations for indoor environment design and control using ordinary office computers. We analyze two representative test cases, which imitate common indoor airflow configurations, on a wide range of different turbulence models and discretizations methods, to meet the requirements for the computational cost, run-time, and accuracy. We consider statistically steady-state simulations for indoor environment design and transient simulations for control. Among studied turbulence models, the no-model and large-eddy simulation with staggered discretizations show the best performance. We conclude that high-fidelity CFD simulations on office computers are too slow to be used as a primary tool for indoor environment design and control. Taking into account different laws of computer growth prediction, we estimate the feasibility of high-fidelity CFD on office computers for these applications for the next decadesThis work is supported by the Ministerio de Economía y Competitividad, Spain [ENE2017-88697-R]. N. Morozova is supported by the by the Ministerio de Economía y Competitividad, Spain [FPU16/06333 predoctoral contract]. Part of the calculations was performed on the MareNostrum 4 supercomputer at the Barcelona Supercomputing Center [RES project I-2019-2-0021]. The authors thankfully acknowledge these institutions. The authors would also like to thank our colleague MSc Xavier Álvarez Farré for the productive discussions.Peer ReviewedPostprint (author's final draft
Demand model estimation from smartphone data: an application to assert new urbanistic development scenarios
© 2022 Elsevier. This manuscript version is made available under the CC-BY-NC-ND 4.0 license http://creativecommons.org/licenses/by-nc-nd/4.0/The pervasive use of mobile devices has brought a valuable new source of data. The work presented here has a twofold objective: firstly, to demonstrate the capability of mobile phone records to feed traditional trip-based demand models and, secondly, to assert the possibilities of using developed models to estimate the effects of new urbanistic development scenarios. Detailed trip data for the metropolitan area of Barcelona are reconstructed from mobile phone records. This information is then employed as input for building a set of demand trip-based models and to apply these daily-based models to the appraisal of new development scenarios in a VISUM model of the city. The model calibration and validation process proves the quality of the models obtained. Our results show the way in which the generated trips are distributed into the study area and modal share is modified in the considered scenarios.This research was funded by TRA2016-76914-C3-1-P Spanish R+D Programs, Secretaria d’Universitats-i-RecercaGeneralitat de Catalunya- 2017-SGR- 1749. The authors are grateful for the support given by the Autoritat del Transport Metropolità (ATM) providing us with their model (Ll. Alegre, F. Calvet, and X. Sanyer). We are also grateful to Dra. L. Pagés (CARNET-UPC), J. Llinàs and A. Ortiz (Barcelona Regional) for their support.Peer ReviewedObjectius de Desenvolupament Sostenible::11 - Ciutats i Comunitats SosteniblesObjectius de Desenvolupament Sostenible::10 - Reducció de les DesigualtatsPostprint (published version
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