1,137 research outputs found

    A utilização de RCD (Resíduos de Construção e Demolição) na construção: exemplo prático da Península de Troia

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    Ao longo das últimas décadas assistimos à destruição de enormes manchas verdes com o intuito de explorar os maciços rochosos sob estas, a partir dos quais se produzem os agregados necessários à utilização na construção civil e nas obras públicas. Porém, nos últimos anos, esta situação tem vindo a inverter-se, assistindo-se, cada vez mais, a uma preocupação global na mitigação do impacte ambiental de tal exploração desenfreada e na redução dos custos da construção. A península de Troia foi um dos mais significativos exemplos na mitigação dessas preocupações, tendo-se reutilizado 109.200 m3 de resíduos de construção e demolição na construção de novos arruamentos, na base de edifícios, na execução de poços drenantes e em infraestruturas provisórias, dos cerca de 130.700 m3 de diversos tipos de resíduos produzidos, representando uma reutilização a rondar os 92%. Pretende-se com esta dissertação, apresentar uma vertente de valorização dos RCD demonstrando as vantagens na sua reutilização, sem deixar de dar a conhecer um pouco melhor a Península de Troia, outrora tão importante nas rotas comerciais, o atual ponto de situação relativo à reutilização de RCD, assim como as atuais questões legais pelas quais se rege, atualmente, a utilização de Resíduos de Construção e Demolição

    Classe de Ciências

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    info:eu-repo/semantics/publishedVersio

    Classe de Ciências

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    info:eu-repo/semantics/publishedVersio

    Additive manufacturing of technical ceramics

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    Additive Manufacturing (AM) is an area intrinsically linked to industry 4.0 because of its ability to meet some of the most significant challenges in the industry such as production of custom parts, complex geometries and direct processing (through cloud manufacturing). Due to its advantages, the market for functional parts based on inorganic materials via AM is in great development. The present study has focused on the Fused Deposition of Ceramics (FDC) process, which is suitable, in combination with post-processing steps such as debinding and sintering, for the consolidation of ceramic powder particles from filamentary materials. Although the volume content of ceramic powders is very limited, due to the absence of high pressures, the FDC has been of scientific and industrial interest due to its ability to eliminate some limitations imposed by other processes such as Selective Laser Melting (SLM), due to the sources of high energy consumption, and Powder Injection Molding (PIM), due geometric and mold cost limitations. The major challenges of this dissertation involved producing filaments for FDC, based on PIM or powder extrusion (PE) methodologies, joining the filaments of feedstock with optimized ratios of tungsten carbide powder (48.5%vol.) that should withstand the stresses involved in the FDC extrusion, and providing suitable extrusion fluidity. Afterwards, the challenges were overcome and the shaped parts through FDC were debinded and sintered. These processes led to the production of near net shape WC-10Co parts with characteristics and properties close to those resulting from conventional replicative processes of the powders

    Technology evaluation and licensing : a literature review and an assessment of the Portuguese universities technology transfer practices

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    To improve the access to information about practices supporting the application of research results we looked at strategies and methods described on the literature review and in use by technology transfer units (TTUs) having in mind a set of questions underlying the processes of technology evaluation and licensing in universities. The research questions gave us the opportunity to understand the TTUs degree of selectivity in the protection of inventions, the factors at the origin of licensing agreements and its main obstacles, the main evaluation methods and payment modes and they also gave us the opportunity to know the universities at study structure of dividend distribution. Underneath the answer to this questions we affirmed that the development of complete and demonstrable turnkey solutions and products decreases the investment risk and makes the technology more attractive to potential licensees, and we concluded that only knowing the economic value of an invention can we fully exploit its full potential and can we carry out an appropriate technology valorization strategy.Fundação para a Ciência e a Tecnologia (FCT

    A study on the performance of technology transfer units

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    Universities are increasingly institutionalizing activities related to technology transfer and one of the main institutional mechanisms that has emerged is the “technology transfer unit” (TTU). Many of them are focusing their activities on the management of the university intellectual property. Studies have investigated factors that seem to affect their performance, but few have looked in detail at internal procedures and techniques that are used in their processes related to technology evaluation and licensing. The aim of this paper is to provide a comprehensive overview of some of the several steps that comprises the processes regarding technology evaluation and licensing, providing an analysis of the critical issues that affect each step of the process. A review of the literature was made, complemented with interviews to seven university TTUs, which was used as a check and a complement to the literature review and as way of perceiving from an insider perspective, the problems and issues that this paper wants to emphasize and to state clearly
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