14 resultados para Glass industry
em Universidade do Minho
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Natural Fiber Composites based on polypropylene have gained increasing interest over the past two decades, both in the scientific and industry communities. In this study, the mechanical properties of polypropylene (PP)/natural fiber composites were studied and compared with those of polypropylene reinforced by glass fiber. Flax and jute woven fabrics have been used. PP/glass fiber composites showed better performance in terms of tensile properties.
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During recent decades it has been possible to identify several problems in construction industry project management, related with to systematic failures in terms of fulfilling its schedule, cost and quality targets, which highlight a need for an evaluation of the factors that may cause these failures. Therefore, it is important to understand how project managers plan the projects, so that the performance and the results can be improved. However, it is important to understand if other areas beyond cost and time management that are mentioned on several studies as the most critical areas, receive the necessary attention from construction project managers. Despite the cost and time are the most sensitive areas/fields, there are several other factors that may lead to project failure. This study aims at understand the reasons that may cause the deviation in terms of cost, time and quality, from the project management point of view, looking at the knowledge areas mentioned by PMI (Project Management Institute).
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Nowadays, organizations are increasingly looking to invest in business intelligence solutions, mainly private companies in order to get advantage over its competitors, however they do not know what is necessary. Business intelligence allows an analysis of consolidated information in order to obtain more specific outlets and certain indications in order to support the decision making process. You can take the right decision based on the data collected from different information systems present in the organization and outside of them. The textile sector is a sector where concept of Business Intelligence it is not many explored yet. Actually there are few textile companies that have a BI platform. Thus, the article objective is present an architecture and show all the steps by which companies need to spend to implement a successful free homemade Business Intelligence system. As result the proposed approach it was validated using real data aiming assess the steps defined.
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The present work focuses on the use of the life cycle assessment (LCA) and life cycle costing (LCC)methodologies to evaluate environmental and economic impacts of polymers and polymer composites materials and products. Initially a literature review is performed in order to assess the scope and limitations of existing LCA and LCC studies on these topics. Then, a case study, based on the production of a water storage glass-fibre reinforced polymer (GFRP) composite storage tank, is presented. The storage tank was evaluated via a LCA/LCC integrated model, a novel way of analysing the life cycle (LC) environmental and economic performances of structural products. The overarching conclusion of the review is that the environmental and economic performances of polymers composites in non-mobile applications are seldom assessed and never in a combined integrated way.
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A flexible and low cost energy harvester device based on the magnetoelectric (ME) effect has been designed using Fe64Co17Si7B12 as amorphous magnetostrictive ribbons and PVDF as the piezoelectric element. Sandwich-type laminated composite of 3 cm long has been fabricated by gluing these ribbons to the PVDF with the Devcon 5 minute epoxy. Good power output and power density of 6.4 μW and 1.5 mW/cm3, respectively, have been obtained through a multiplier circuit. All values have been measured at the magnetomechanical resonance of the laminate. The effect of the length of the ME laminate on the power output has been also studied, exhibiting a decay as the length of the ME laminate does. Nevertheless, good performance of such device has been obtained for a 0.5 cm long device, working already at 337 KHz, within the low radio frequency (LRF) range.
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Companies and researchers involved in developing miniaturized electronic devices face the basic problem of the needed batteries size, finite life of time and environmental pollution caused by their final deposition. The current trends to overcome this situation point towards Energy Harvesting technology. These harvesters (or scavengers) store the energy from sources present in the ambient (as wind, solar, electromagnetic, etc) and are costless for us. Piezoelectric devices are the ones that show a higher power density, and materials as ceramic PZT or polymeric PVDF have already demonstrated their ability to act as such energy harvester elements. Combinations between piezoelectric and electromagnetic mechanism have been also extensively investigated. Nevertheless, the power generated by these combinations is limited under the application of small magnetic fields, reducing the performance of the energy harvester [1]. In the last years the appearance of magnetoelectric (ME) devices, in which the piezoelectric deformation is driven by the magnetostrictive element, enables to extract the energy of very small electromagnetic signals through the generated magnetoelectric voltage at the piezoelectric element. However, very little work has been done testing PVDF polymer as piezoelectric constituent of the ME energy harvester device, and only to be proposed as a possibility of application [2]. Among the advantages of using piezopolymers for vibrational energy harvesting we can remember that they are ductile, resilient to shock, deformable and lightweight. In this work we demonstrate the feasibility of using magnetostrictive Fe-rich magnetic amorphous alloys/piezoelectric PVDF sandwich-type laminated ME devices as energy harvesters. A very simple experimental set-up will show how these laminates can extract energy, in amounts of μW, from an external AC field.
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During the recent years followed by the Global Financial Crisis (GFC), most of business and industries around the globe have been hardly hit to the limit that it still struggling to survive, suffering from the crisis financial consequences. For instance, in the construction industry; many construction projects have been suspended or totally cancelled. Nevertheless, among this dilemma, a call has been raised to use the sustainable practices to mitigate the effects of the GFC on construction industry. For the first look, it seems that there is contradiction since the sustainable solutions are often associated with an increase in the initial cost, undoubtedly, the sustainable practices have many advantages in both economic and environment aspects, however, the question which needs to be addressed here is, to what extent using such sustainable practices can mitigate the negative effects of the economic downturn on construction industry. Therefore, it is a challenging argument for using such sustainable construction from its economic perspective, however, this paper is aiming to present the economical benefits of sustainable practices in construction industry, and trying to clear the doubt of the high initial costs of the sustainable construction through studying the life cycle benefit of green building.
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Dissertação de mestrado integrado em Engenharia e Gestão Industrial
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Proceedings da AUTEX 2015, Bucareste, Roménia.
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ICEIM – International Conference in Entrepreneurship and Innovation Management, Roma, 17-18 de setembro de 2015.
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Dissertação de mestrado integrado em Engenharia Biomédica (área de especialização em Engenharia Clínica)
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Dissertação de mestrado integrado em Engenharia Civil
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Biofilms in food processing plants represent not only a problem to human health but also cause economic losses by technical failure in several systems. In fact, many foodborne outbreaks have been found to be associated with biofilms. Biofilms may be prevented by regular cleaning and disinfection, but this does not completely prevent biofilm formation. Besides, due to their diversity and to the development of specialized phenotypes, it is well known that biofilms are more resistant to cleaning and disinfection than planktonic microorganisms. In recent years, a considerable effort has been made in the prevention of microbial adhesion and biofilm formation on food processing surfaces and novel technologies have been introduced. In this context, this chapter discusses the main conventional and emergent strategies that have been employed to prevent bacterial adhesion to food processing surfaces and thus to efficiently maintain good hygiene throughout the food industries.
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The prelims comprise: * Half-Title Page * Dedication Page * Title Page * Copyright Page * Table of Contents * Foreword * Acknowledgements * Disclaimer * Introduction