Development of the in situ forming of a liquid infused preform (ISFLIP) process : a new manufacturing technique for high performance fibre reinforced polymer (FRP) components

A problem is not a problem anymore if no solution exists; therefore, in the present dissertation, a novel manufacturing technique, the In Situ Forming of a Liquid Infused Preform (ISFLIP), is proposed as a solution to some typical problems that manufacturing of Fibre Reinforced Polymer (FRP) parts through Vacuum Infusion (VI) involves, such as not taking advantage of the full potential of FRPs, long processing times and lack of reproducibility. ISFLIP is a hybrid process between VI and diaphragm forming in which a flat preform of a stack of reinforcement fabrics is firstly impregnated with a low viscosity matrix and, then, formed over a mould while the matrix is still in the low viscosity state. Being focused on high performance FRPs and shell components, from simple to complex double curvature shapes, a number of trade-offs between VI and diaphragm forming were overcome to lay the foundations from which ISFLIP ability to manufacture FRP components has been proven. In order to adopt a VI manufacturing methodology that fitted ISFLIP targets, important contributions to more general VI have also been made in terms of part quality optimization, addressing the major concern that void content is in VI, with competitive manufacturing times. An effective vacuum degassing procedure in which bubble formation is enhanced through high speed stirring, and a non-conventional filling and post-filling strategy are proposed for this purpose. Eventually, void content was virtually eliminated and post-filling time minimized without affecting fibre content. In ISFLIP, textile preforms are formed together with a series of auxiliary materials (plastic films and sheets, textile fabrics and knitted meshes), most of them showing different in-plane deformation mechanisms. Forming performance of preforms, as well as final part quality, are severely affected by interactions between all these materials different in nature. Uncertainties on this respect and an initial evaluation of attainable shapes were also addressed to define a more focused research plan to the final goal, still distant, of implementing ISFLIP in a real production environment. Results obtained throughout the research project give cause for reasonable optimism in ISFLIP potential and future prospects.Un problema deja de ser un problema si no existe solución; por lo tanto, en esta disertación, una novedosa técnica de fabricación, el Conformado In Situ de una Preforma Infusionada con resina Líquida (ISFLIP, por sus siglas en inglés), se propone como solución a algunos problemas típicos relacionados con la fabricación de piezas de Polímero Reforzado con Fibra (FRP) a través de la Infusión por Vacío (VI), problemas tales como el desaprovechamiento de todo el potencial de los FRPs, largos tiempos de procesado y falta de reproducibilidad. ISFLIP es un proceso híbrido entre la VI y el conformado por membrana elástica en el que una preforma plana formada a partir de un apilado de tejidos de refuerzo es en primera instancia impregnada con una resina de baja viscosidad y, entonces, conformada sobre un molde mientras que la matriz permanece todavía en el estado de baja viscosidad. Estando centrado en los FRPs de altas prestaciones y en componentes con formas tipo concha, desde curvaturas simples hasta formas con doble curvatura complejas, un número importante de compensaciones entre la VI y el conformado por membrana se han ido superando para asentar las bases a partir de las cuales se ha probado la capacidad de ISFLIP para fabricas componentes de FRP. Con la vista puesta en implementar una metodología de fabricación por VI que cumpliese los objetivos definidos para ISFLIP, también se han realizado importantes contribuciones de carácter más general relacionadas con la VI en términos de optimización de parámetros de calidad de las piezas, abordando la gran preocupación que la porosidad final supone en la VI, y consiguiendo unos tiempos de fabricación competitivos. Con este propósito se han propuesto un proceso de desgasificación por vacío muy efectivo en el que se favorece la nucleación de burbujas mediante la agitación a alta velocidad, y una prometedora y no convencional estrategia de llenado y post-llenado de la preforma. Finalmente, se consiguió virtualmente eliminar la porosidad atrapada en las piezas, minimizando el tiempo de post-llenado sin afectar la fracción de fibra contenida. En ISFLIP las preformas textiles se conforman junto con una serie de materiales auxiliares (films y hojas plásticas, mallas y tejidos textiles), que muestran diferentes mecanismos de deformación en plano. El conformado de las preformas y el acabado final de las piezas se ve severamente afectado por todas las interacciones entre todos estos materiales diferentes en naturaleza. También se han abordado las incertidumbres que surgen al respecto y una evaluación inicial de las geometrías abarcables para definir un plan de investigación más concreto con el que poder afrontar la meta final, todavía distante, de implementar ISFLIP en un entorno productivo real. Los resultados obtenidos a lo largo de este proyecto de investigación permiten ser razonablemente optimistas en cuanto al potencial de ISFLIP y sus expectativas

Una propuesta curricular para la implementación de un taller de aplicaciones matemáticas en ingeniería

Dentro del marco teórico de la enseñanza por proyectos (La Cueva, 2001; Malaspina, 2007), se presenta una asignatura curricular llamada taller de aplicaciones matemáticas en la cual se realizan aplicaciones generales de tipo básico, aplicaciones relacionadas con la ingeniería en general y aplicaciones específicas a cada tipo de ingeniería de las impartidas en la Unidad Profesional Interdisciplinaria de Biotecnología (UPIBI). Los alumnos hacen uso de sus antecedentes matemáticos y resuelven problemas de aplicación en un ambiente cooperativo, construyen por si mismos los modelos de los problemas a resolver. Se trabaja y evalúa por medio de proyectos en los cuales se fomenta el aprendizaje cooperativo, el compromiso de los estudiantes y la creatividad. La evaluación es continua, las tareas son proyectos cortos y no hay exámenes. Los alumnos preparan por equipo un proyecto más extenso que prepara en una o dos semanas y cuyos resultados presentan en una sesión pública donde son evaluados a partir de la presentación, de la entrega detallada de un reporte escrito con sus resultados y de su desempeño en la sesión de preguntas. Además de la propuesta se presentan resultados preliminares porque ya se implementado la asignatura

Un sistema ERP para las pyme en América Latina: Revisión de literatura

Introduction: This article is supported by the research and bibliographic review carried out during February and April 2020 in the Industrial Engineering program of the Fundación Universitaria de Popayán C.Problem: Small and Medium-sized Enterprises (SMEs) are faced with various challenges, to the extent that they do not have technological systems that allow them to administer and manage the information that each area can generate in a timely and practical manner, preventing them from effectively planning for the future.Objective: The Bibliographic review aims to establish what type of ERP system would serve SMEs in Latin America, so that they can be combined with the organization’s strategies, seeking to optimize and improve production processes.Methodology: The bibliographic review was carried out applying Kitchenham’s guidelines, which proposes three fundamental stages: (1) planning the review, (2) development of the review, and (3) publication of the review results. Results: For SMEs, cloud-managed openERPs represent a viable option, since implementation costs are signi-ficantly reduced, as well as the issue of maintenance and technical support.Conclusion: OpenERP systems managed in the cloud represent the most feasible option, due to costs, prac-ticality, flexibility and lower operational requirements when implementing the implementation of the system.Este es un artículo de revisión de literatura, donde se consultaron las siguientes bases de datos: Google Scholar, EBSCO, IEEE Explore y ScienceDirect, obteniéndose un total de 100 coincidencias de búsqueda, con el objetivo de determinar la factibilidad que involucra la implementación de un sistema ERP en PYMES. De estos artículos encontrados se realizó un filtro teniendo en cuenta una serie de criterios, quedando un total de 61 artículos, de los cuales a los que abordaban algún tipo de sistemas ERP, se le analizaron factores como: costos, tiempo de implantación, flexibilidad y adaptabilidad. Con base a los resultados encontrados se pudo determinar teniendo presente también puntos de vista de varios autores, que el sistema tecnológico que más le conviene a las PYMES en América Latina, es el sistema Open ERP ODOO que sea gestionado por la nube, ya que permite ahorrar dinero, tiempo en la implementación y se puede ajustar a las necesidades de la empresa

Recursos endógenos mineros y desarrollo territorial. El caso de la comarca del Mármol (Almería, España)

La comarca del Mármol, en Almería, posee el mayor yacimiento de España de esta roca ornamental. Gracias a los planes de desarrollo de las últimas décadas del pasado siglo, es de los pocos territorios interiores de Andalucía con una destacada actividad industrial y que ha conseguido fijar la población. El clima empresarial generado ha impulsado la investigación, apostando por la calidad y abriéndose al exterior, y ha introducido en el mercado nuevos productos no basados en el mármol, que son de gran ayuda para la sostenibilidad de la actividad económica. El distrito industrial que conforman estas empresas ha evolucionado, ajustándose a las circunstancias y mostrando una elevada resiliencia. Economic globalisation and the resulting proximity between countries and regions, have not only failed to obliterate local areas, but have indeed highlighted their relevance. In parallel with the evolution of the globalising process, and in numerous cases, the territorial dimension has increased in value, as a necessary pillar for progress and for the benefit of the population, driven by development programmes, in which endogenous resources and sustainability are paramount. One of the bases of this process lies in the rescue by Becattini of the Marshallian industrial district, which explains the success of small and medium enterprises (SMEs) is specialised production systems. In the north of the Almería province, in the Filabres mountain range, exist the greatest marble quarries in the whole of the Spanish territory, both in terms of volume and of quality the set of towns and villages located in the area where this natural resource is extracted and processed is known as the Marble Region. The best known variety is Macael white marble, which has been quarried since the first centuries of our era and has been used to beautify a vast number of constructions, among them the Alhambra in Granada and the Monastery of El Escorial. From an analysis of the history and evolution of the marble industry in the area, the following landmarks need to be highlighted. Until the end of the first third of the 19th century, marble was a communally owned asset, which led to the proliferation of a number of very small quarries. The transition to private ownership and therefore to local council management, was unable to stop the surge of smallholds, from which other problems derived, such as the use of poor technical means and the chaos caused by waste/rubble dumps, characteristics that have plagued this sector for almost a century and a half. During the first decades of the second half of the 20th century, extraction was carried out in many quarries with very small fronts, by reticent entrepreneurs who were reluctant to invest, since their rights to open shaft mining had a time limit, established in the permit granted by the local council, which was the owner of the terrain and of the mining concessions. This is one of the reasons which explain why nearly all quarry workers/entrepreneurs were local, with hardly any presence of capital from outside. The marble processing panorama was very similar; small factories and workshops predominated with a reduced capacity for production and dated machinery, unable to supply demands for quality and quantity, and thus with scarce commercial potential. As the decade of the 80s started, the marble industry, weighed down by its own internal problems, worsened due to decreasing demand and to the precarious economic situation in general, had sunk in a deep crisis. In those years, public administration in agreement with agents and local institutions, and counting on their total involvement, set in motion several local development plans that proved to be crucial in modernising the marble industry in Macael. In 1983, an Action Plan was initiated and in 1996 a Strategic Plan. The industrial restructure undertaken changed the entrepreneurial scene completely. In the extraction area, the Plan Director de la Sierra de Macael (Macael Mountain Range Director Plan) introduced “business units” —areas of similar characteristics consisting of several quarries— which by unifying various tasks, allowed for a more rational mechanisation, improved continuity in marble supply, better organised enterprises and increased safety. A vastly improved use of resources, together with lower extraction costs, increased the lifespan of the marble deposits (Carretero, 1995: 345-346). With regard to product transformation, the restructure laid down the foundations for resizing the companies and updating the technology; many microenterprises that produced building materials and were hardly able to compete with any success were re-orientated towards craftsmanship. Besides tackling the problems of the companies and their infrastructure, the plans also considered people, promoting training and so an optimistic atmosphere was created, with expectations that spurred the initiatives of many entrepreneurs and encouraged common initiatives. Thanks to these strategies, local development, which until then had been a crowd of quarries, was transformed into an industrial district with great drive and resilience. When the 20th century gave way to the 21st, other definitely competitive advantages were added to the comparative advantage of possessing a unique natural resource, (research and innovation, qualified and specialised staff, very high quality finished products, marketing channels). The district had ceased to be an extraction centre to become a product processing and transformation centre, both from local and external quarries, which reduced their dependence on local raw materials and acquiring higher value and better offers. In this process, international expansion has played a vital role, based on research and innovation carried out by one of the companies, Cosentino, during the decade of the 80s and that would become a world leading firm for artificial agglomerates, hardly using any local raw materials. Around the middle of the second decade of the 21st century, the composition of the district is very different from what it was 20 years ago. A great dominant enterprise, Cosentino, has made it presence felt, producing an income level from the factory located in the area that represents 90, 8% of the whole district, around 12 small enterprises, of which only 4 employ more than 20 workers and have a relevant external projection, and a pack consisting of scores of microenterprises, which in many cases carry out work for the ones previously mentioned. Although Cosentino carries a lot of weight in the district, around del 95% of its billing is due to artificial agglomerates (Silestone, Dekton…), which places it in a particular situation, since the activity of the other companies revolves around marble extraction, processing and transformation. Besides the employment it generates, Cosentino’s decision to maintain its headquarters and a considerable part of its activities within the district has had a highly positive impact, like the support and collaboration it offers other companies in different areas or its involvement in educational or sociocultural projects, etc. Furthermore, because of its size, it is the main funding entity of professional institutions and associations of which it is a member and has attracted important public investment that has improved services and infrastructure. On the other hand, the firm commitment of the leading companies to offer a first class product, together with their on-site location, and their efforts to increase their presence in outside markets, has developed activities in collaboration with smaller companies, a situation which is yielding very positive results. Recognition of Macael marble, as protected geographical indication (PGI) which is currently being processed and is expected to come through in the near future, will guarantee its high quality, facilitate product differentiation and protect it from dishonest competition. Regardless of the difficulties that this activity has encountered through time, due to the long standing link of the district inhabitants with the marble industry that has spread through centuries, it has a strong socio-territorial component, with an important presence of supporting activities, a highly specialised labour market with firm social and cultural connections. All these occurrences, which remind us of the Marshallian district, where “the mysteries of the trade become no mysteries, but are as it were in the air and children learn many of them unconsciously” Alfred (Marshall, 1890: 198 The Principles of Economics), a theory that can be matched with no difficulty to the properties that Becattini attributes to industrial areas, “socioterritorial entity characterised by the active presence of both a community of people and a population of firms in one naturally and historically bounded area…the community and the firms tend as it were to merge” (Becattini, 1992: 62-63). As it has occurred in other cases, the evolution of the district has led to the surge of a great enterprise in its midst, in this case, a multinational leading company in its products, which at the same time drives the whole set up and hardly uses any local raw material in its preparation process. On the other hand, history reflects the high capability and resilience demonstrated by the district’s population. There are several issues that cannot be disregarded when considering the future of the area and of the socioeconomic development of the Marble Region. These appear to depend on Cosentino’s prestige and relevance. What would happen if it failed? What long-term measures could be taken to minimise the impact of a possible decrease in activity? Due, for example to the relocation of part of its activities? It is important to bear in mind that Cosentino is at present a first generation family business

Context-aware Assessment Using QR-codes

In this paper we present the implementation of a general mechanism to deliver tests based on mobile devices and matrix codes. The system is an extension of Siette, and has not been specifically developed for any subject matter. To evaluate the performance of the system and show some of its capabilities, we have developed a test for a second-year college course on Botany at the School of Forestry Engineering. Students were equipped with iPads and took an outdoor test on plant species identification. All students were able to take and complete the test in a reasonable time. Opinions expressed anonymously by the students in a survey about the usability of the system and the usefulness of the test were very favorable. We think that the application presented in this paper can broaden the applicability of automatic assessment techniques.The presentation of this work has been co-founded by the Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech

Ensayo metodológico de cartografía de zonas expuestas a riesgos de caídas de materiales: Las Trancas-Termas de Chillán (VIII Región) - Chile

El problema de los riesgos ligados a los movimientos del suelo en Chile, tiene una importancia particular dada las condiciones geomorfológicas desfavorables que existen en diferentes zonas del territorio nacional, especialmente en aquellas que presentan un re lieve montañoso y por la importancia de la creciente presión urbanística que dichas zonas soportan.Se presenta en este artículo una proposición de metodología cartográfica de riesgos de caídas de materiales, a lo largo de vías de comunicación, con aplicación a la ruta 55 en 11 kms. del tramo Las Trancas-Termas de Chillán, en un ambiente de media montaña, en la Provincia de Ñuble, VIII Región del país. Se trata de un avance en la metodología, pues ésta requiere de mayor profundidad en los elementos que se han considerado y de otros no tomados en cuenta aquí y que dicen relación en forma más específica a los aspectos de protección.Estudios sobre este riesgo y sobre otros relativos a movimientos del suelo, han comenzado recientemente en Chile. Estos, diferentes entre ellos pero todos presentando un interés metodológico, permanecen heterogéneos a nivel nacional y aislados a nivel regional, lo que no permite concebir aún aplicaciones prácticas en distintos niveles de gestión, a lo que se agrega una información d esigual de un territorio a otro, así como de sus especificidades

Effect of Bentonite Addition to Pedro Ximénez White Grape Musts before Their Fermentation with Selected Yeasts on the Major Volatile Compounds and Polyols of Wines and Tentative Relationships with the Sensorial Evaluation

In this work, we study the effect of bentonite addition to the grape must before alcoholic fermentation on the chemical composition and sensorial profile of the obtained wines. Fermentations were carried out with two Saccharomyces cerevisiae commercial active dry yeasts treated or not with bentonite and were compared with a control wine obtained by spontaneous fermentation (using the grape must microbiota). Several significant effects on the chemical and sensorial attributes were established by statistical treatments. The selection by multiple variable analysis of seven volatile molecules (ethyl acetate; methanol; 1-propanol; isobutanol; 2-methyl-1-butanol; 3-metyl-1-butanol and 2-phenylethanol) provided several footprints that provide an easy visualization of bentonite effects on wine volatile compounds. A Principal Component Analysis carried out with all the compounds quantified by Gas-Chromatography revealed that the first two Principal Components explain 60.15 and 25.91%, respectively, of the total variance and established five groups that match with the five wines analyzed. Lastly, predictive models at p ≤ 0.05 level for the attributes sight, smell and taste were obtained by Partial Least Squared regression analysis of selected chemical variables

Design of a prototype for the in situ forming of a liquid infused preform (ISFLIP) process

The world is changing and demanding stronger, lighter and more versatile materials. Taking advantage of the full potential of these materials also requires versatile manufacturing processes. The in situ forming of a liquid infused preform (ISFLIP) is a new manufacturing process for fiber reinforced polymer (FRP) parts with shell shapes. ISFLIP is a hybrid process between vacuum infusion (VI) and diaphragm forming. This paper focuses on the mechanical design and experimental validation of a functional prototype of ISFLIP. The novelty of the design lies especially in a double diaphragm system that is fundamental to carrying out the forming just after the infusion stage. The double diaphragm system and other two major subsystems, a vacuum table and an infrared heating grid, were devised to benefit from the operational advantages of ISFLIP. The whole prototype, once constructed, was tested by forming some demonstration components. The result of one of these components, a ‘C’ cross-section FRP profile with two sharp joggles, is finally obtained, proving the feasibility of the prototypePostprint (author's final draft

Arquitecto versus Doctor Arquitecto: las escuelas de arquitectura y el siglo XXI

El objetivo de este trabajo es la realización de un estudio sobre la formación doctoral de arquitectos que contribuya a mejorar la calidad de los programas de doctorados en las Escuelas de Arquitectura españolas y que nos aproxime al Espacio Europeo de Educación Superior y de Investigación. El periodo analizado es el formado por los últimos nueve años: lo transcurrido del siglo XXI. El estudio se ha realizado sobre las Escuelas de Arquitectura de ocho universidades españolas, las que nos han proporcionado la relación de tesis leídas en sus Escuelas de Arquitectura en ese periodo, sus autores y directores. Se ha elaborado una base de datos de las mismas, así como una ficha-modelo que se ha remitido a los autores de esas tesis, recabándole información diversa: tiempo de duración de la tesis, financiación obtenida para su desarrollo, movilidad nacional e internacional, publicaciones derivadas, doctorado europeo, etc. A partir de este estudio se presentan conclusiones sobre el estado actual de la formación doctoral en Arquitectura