ISEP - Departamento de Engenharia Mecânica
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- Filosofias da Qualidade (Quality Gurus) - desenvolvimento de uma cultura da qualidade na empresaPublication . Fonseca, LuísSão analisadas as principias metodologias e abordagens de Deming, Juran, Crosby, Ishikawa e Taguchi, visando identificar quais as mais adequadas para diversos tipos de cultura organizacional.
- Responsabilidade Social e Desenvolvimento Sustentável: moda passageira ou requisito para sobrevivência?Publication . Fonseca, LuísA Responsabilidade Social e o Desenvolvimento Sustentável através da procura simultânea de crescimento económico lucrativo, progresso e equidade social e respeito pelo meio ambiente, visam dar resposta aos grandes desafios actuais da humanidade, tais como o crescimento populacional, o combate à pobreza e às alterações climáticas e a existência de recursos naturais limitados. Após estabelecer um quadro de referência de conceitos e abordagem teórica, é proposta uma reflexão sobre as Motivações, Acções e eventuais Limitações da Responsabilidade Social e da Sustentabilidade, de modo a que cada um responda à questão proposta: Responsabilidade Social e Desenvolvimento Sustentável: moda passageira ou requisito para a sobrevivência?
- Gestão da Qualidade: uma reflexão crítica e actualPublication . Fonseca, LuísDe uma forma sintética, a Gestão da Qualidade assenta em “3 pilares”, cada um desenvolvido por diferentes autores e com diferentes destinatários durante a década de 1980 e o início da década seguinte: a visão dos Gurus, o movimento das normas da série ISO 9000 e os Modelos de Excelência Empresarial. É efectuada uma análise crítica dos mesmos e apontadas pistas para uma possível evolução holística da Qualidade visando a vantagem competitiva e o sucesso sustentável das organizações e a satisfação dos seus stakeholders.
- Impact of Social Responsibility Programmes in Stakeholder Satisfaction: An Empirical Study of Portuguese Managers’ PerceptionsPublication . Fonseca, Luís; Ramos, Amílcar; Rosa, Álvaro; Braga, Ana Cristina; Sampaio, PauloThis study investigates the relationship between social responsibility programmes of organizations and stakeholder satisfaction. Based on stakeholder theory, an online survey was administered to managers of Portuguese organizations with certified management systems. The findings suggest that stakeholder satisfaction is indeed increased with a social responsibility programme, as suggested by Freeman’s stakeholder theory. The components of social responsibility programmes that we discussed in this paper comprehend, among others, the “best governance practices”, “best customers, suppliers and partners management practices” and “best social inclusion and society support and relationship practices”, and do provide a balanced and continuously satisfaction to the different sets of stakeholders as shown by our survey results.
- Responsabilidade Social influencia sucesso sustentável das organizaçõesPublication . Fonseca, LuísAs metodologias usadas para caracterizar e quantificar a Responsabilidade Social das organizações e o seu contributo para o sucesso sustentável das mesmas não reúnem consenso. É por isso difícil obter indicadores económicos, financeiros, de mercado e de responsabilidade social que sejam credíveis. Com este trabalho, realizado no âmbito da tese de doutoramento “Influência da Responsabilidade Social das Organizações para o seu Sucesso Sustentável”, procurou- se investigar se as teorias, os conceitos e as metodologias que fundamentam a Responsabilidade Social das organizações são suportadas pelos seus próprios gestores e se estes consideram que estão a contribuir para o sucesso sustentável das suas organizações e ao mesmo tempo para o desenvolvimento sustentável da sociedade e do planeta. Aqui ficam as principais conclusões.
- Mapeamento da Responsabilidade Social em Portugal (The Mapping of Social Responsibility in Portugal)Publication . Fonseca, LuísO objetivo desta investigação consistiu em mapear os conceitos e ferramentas de Responsabilidade Social das organizações portuguesa. Concluiu-se que para os respetivos gestores os esforços dos programas de Responsabilidade Social ou equivalentes têm-se traduzido em melhorias significativas na satisfação das diversas partes interessadas com destaque para os clientes e menor sucesso para os empregados e que os mesmos consideram a Responsabilidade Social e a Sustentabilidade como relevantes na estratégia de negócio para aumentar e proteger o valor da organização aque pertencem.
- Tensile behaviour of a structural adhesive at high temperatures by the extended finite element methodPublication . Campilho, Raul; Banea, Mariana D.; Silva, Lucas F. M. daComponent joining is typically performed by welding, fastening, or adhesive-bonding. For bonded aerospace applications, adhesives must withstand high-temperatures (200°C or above, depending on the application), which implies their mechanical characterization under identical conditions. The extended finite element method (XFEM) is an enhancement of the finite element method (FEM) that can be used for the strength prediction of bonded structures. This work proposes and validates damage laws for a thin layer of an epoxy adhesive at room temperature (RT), 100, 150, and 200°C using the XFEM. The fracture toughness (G Ic ) and maximum load ( ); in pure tensile loading were defined by testing double-cantilever beam (DCB) and bulk tensile specimens, respectively, which permitted building the damage laws for each temperature. The bulk test results revealed that decreased gradually with the temperature. On the other hand, the value of G Ic of the adhesive, extracted from the DCB data, was shown to be relatively insensitive to temperature up to the glass transition temperature (T g ), while above T g (at 200°C) a great reduction took place. The output of the DCB numerical simulations for the various temperatures showed a good agreement with the experimental results, which validated the obtained data for strength prediction of bonded joints in tension. By the obtained results, the XFEM proved to be an alternative for the accurate strength prediction of bonded structures.
- Modelling adhesive joints with cohesive zone models: effect of the cohesive law shape of the adhesive layerPublication . Campilho, Raul; Banea, Mariana D.; Neto, José; Silva, Lucas F. M. daAdhesively-bonded joints are extensively used in several fields of engineering. Cohesive Zone Models (CZM) have been used for the strength prediction of adhesive joints, as an add-in to Finite Element (FE) analyses that allows simulation of damage growth, by consideration of energetic principles. A useful feature of CZM is that different shapes can be developed for the cohesive laws, depending on the nature of the material or interface to be simulated, allowing an accurate strength prediction. This work studies the influence of the CZM shape (triangular, exponential or trapezoidal) used to model a thin adhesive layer in single-lap adhesive joints, for an estimation of its influence on the strength prediction under different material conditions. By performing this study, guidelines are provided on the possibility to use a CZM shape that may not be the most suited for a particular adhesive, but that may be more straightforward to use/implement and have less convergence problems (e.g. triangular shaped CZM), thus attaining the solution faster. The overall results showed that joints bonded with ductile adhesives are highly influenced by the CZM shape, and that the trapezoidal shape fits best the experimental data. Moreover, the smaller is the overlap length (LO), the greater is the influence of the CZM shape. On the other hand, the influence of the CZM shape can be neglected when using brittle adhesives, without compromising too much the accuracy of the strength predictions.
- Fracture toughness determination of adhesive and co-cured joints in natural fibre compositesPublication . Campilho, Raul; Moura, Daniel; Gonçalves, Daniel J. S.; Silva, João; Banea, Mariana D.; Silva, Lucas F. M. daAdhesive bonding has become more efficient in the last few decades due to the adhesives developments, granting higher strength and ductility. On the other hand, natural fibre composites have recently gained interest due to the low cost and density. It is therefore essential to predict the fracture behavior of joints between these materials, to assess the feasibility of joining or repairing with adhesives. In this work, the tensile fracture toughness (Gc n) of adhesive joints between natural fibre composites is studied, by bonding with a ductile adhesive and co-curing. Conventional methods to obtain Gc n are used for the co-cured specimens, while for the adhesive within the bonded joint, the J-integral is considered. For the J-integral calculation, an optical measurement method is developed for the evaluation of the crack tip opening and adherends rotation at the crack tip during the test, supported by a Matlab sub-routine for the automated extraction of these quantities. As output of this work, an optical method that allows an easier and quicker extraction of the parameters to obtain Gc n than the available methods is proposed (by the J-integral technique), and the fracture behaviour in tension of bonded and co-cured joints in jute-reinforced natural fibre composites is also provided for the subsequent strength prediction. Additionally, for the adhesively- bonded joints, the tensile cohesive law of the adhesive is derived by the direct method.
- From Customer to Stakeholder Management: Quality Managers perceptions of Sustainability and Social Responsibility concepts, motivations and impactsPublication . Fonseca, LuísThe research proves that under certain conditions: The economic, environmental and social dimensions are key to organizational sustainable success; Stakeholder satisfaction is significantly higher when a Social Responsibility program is present and it is relevant for the organizational sustainable success and competitive position, as suggested by Freeman (1984) Stakeholder Theory and in line with ISO 9004:2009 and the Excellence Models approaches.