ISEL - Eng. Mecan. - Comunicações
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Browsing ISEL - Eng. Mecan. - Comunicações by Author "Abreu, António"
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- An approach based on fuzzy logic, to improve quality management on research and development centersPublication . Santos, Ricardo; Abreu, António; Calado, João Manuel FerreiraNowadays, with globalization and with the development of emergent economies the Research and Development (R&D) Centres in Europe to survive need to achieve high levels of excellence. In this way, the use of a quality management tools, such as European Foundation for Quality Management (EFQM), can help the managers of such organizations to identify de best practices to enhance the efficiency and effectiveness. Hence, this paper presents a new approach to support managers of R&D centres in the decision-making process in achieving the aims mentioned above, which is based on the EFQM model integrated with Fuzzy Logic. The proposed approach was applied to a Portuguese R&D Centre to assess its overall performance. In order to evaluate the robustness of the proposed approach, the results achieved were compared with the results obtained through a traditional methodology based on RADAR’s Logic.
- An approach to provide efficient choices to a household consumerPublication . Santos, Ricardo; Matias, J. C. O.; Abreu, AntónioIn this work, it will be presented an approach, applied to an energy efficiency problema in buildings, which allows the decision-agent (consumer) to perform a set of efficient choices, suitable to its needs, reducing therefore, the building overall energy consumption during the equipment lifecycle period (usage phase). The approach will use Evolutionary Algorithms (EA), combined with Multicriteria analysis. The quality of EA solutions will be evaluated through the comparison, with the ones, obtained from Simplex method. The EA robustness to the change of its parameters, will also be evaluated, as well as the influence of the objective function on its behavior. The approach can provide the consumer with several and different efficient solutions, with less time than Simplex. I tis also possible to improve the obtained solutions, by choosing adequately the EA`s control parameters, as well the problema formulation.
- An overview of critical chain applied to project managementPublication . Correia, Francisco; Abreu, AntónioThe characterization and assessment of the Critical Chain (CC) approach and the adaptation of the Theory of Constraints (TOC) to Project Management is an important element to help promoting the development of this field. Starting with a brief discussion about the CPM method and PERT method, this paper introduces some discussion about the advantages and disadvantages of the CC concerning to traditional approaches.
- Aplicação da abordagem Six sigma na gestão de redes logística dinâmicasPublication . Abreu, AntónioAtualmente, a necessidade em efetuar operações Logísticas com um elevado nível de eficiência em sistemas cada vez mais complexos requer o acesso a vários tipos distintos de tecnologias e de competências que as pequenas e médias empresas geralmente não possuem. Para fazer face, a estes constrangimentos, de acordo com alguns gestores, a via passa pela dinamização das relações inter-empresariais dando origem à emergência de novas formas organizacionais baseadas em redes de colaboração entre empresas de que as redes logísticas dinâmicas são um exemplo. Este artigo tem como objetivo ilustrar o papel da abordagem Six Sigma Scorecard como instrumento de gestão para a melhoria da qualidade no serviço prestado no contexto de uma rede logística dinâmica. O artigo começa por discutir os princípios da filosofia Six Sigma e do Balanced Scorecard. Em seguida, é discutido de que modo se pode fazer a associação das duas metodologias como instrumento de gestão. Por último, é discutido como é que esta abordagem pode ser aplicada na avaliação das atividades Logísticas no contexto de uma rede logística dinâmica.
- Aplicação da lógica difusa para avaliar o nível lean de uma organizaçãoPublication . Abreu, António; Calado, João Manuel Ferreira; Vargas, JoãoNeste artigo apresenta-se um modelo baseado em lógica difusa com o objectivo determinar o nível lean de uma organização. O modelo desenvolvido assenta numa abordagem de avaliação qualitativa, incluindo bases quantitativas, cujo desenvolvimento foi suportado pela utilização de lógica difusa. O recurso à utilização da lógica difusa justifica-se pela sua capacidade de conseguir lidar com a incerteza e a imprecisão dos dados de entrada, bem como, ser igualmente aplicável na análise de variáveis qualitativas de um sistema, transformando-as em valores quantitativos. Uma grande vantagem do modelo desenvolvido é que este poderá ser reajustado a qualquer tipo de organização independentemente da sua natureza, dimensão, estratégia e posicionamento no mercado. Além disso, o modelo proposto possibilita a identificação de forma sistemática dos factores de constrangimento existentes na organização e fornecer assim a informação necessária para que a gestão desenvolva um plano holístico de melhoria contínua. Visando a avaliação da robustez da abordagem proposta neste artigo, o modelo foi aplicado a uma organização de manutenção e fabricação aeronáutica, sendo apresentados os resultados obtidos e efectuada a correspondente análise crítica dos mesmos. In this paper in order to determine the level of a lean organization a model based on fuzzy logic has been developed. The developed model has been based on a qualitative assessment approach, including quantitative bases, whose development was supported by the use of fuzzy logic. Recourse to the use of fuzzy logic is justified by its ability to cope with uncertainty and imprecision of the input data, as well as, could be applied to the analysis of qualitative variables of a system, turning them into quantitative values. A major advantage of the developed model is that it can be adjusted to any organization regardless of their nature, size, strategy and market positioning. Furthermore, the proposed model allows the identification systematically of constraint factors existing in the organization and thus provide the necessary information for the management to develop a holistic plan for continuous improvement. To assess the robustness of the approach proposed in this paper, the model was applied to a maintenance and manufacturing aeronautical organization, being presented the corresponding results and made a critical analysis of them.
- Aplicação do six sigma business scorecard na gestão de ecossistemas de inovaçãoPublication . Calado, João Manuel Ferreira; Requeijo, José; Abreu, AntónioNo atual contexto, as empresas para serem competitivas têm de desenvolver capacidades de inovação de elevado desempenho que lhes permitam responder rapidamente às necessidades do mercado. No entanto, a ausência de ferramentas e metodologias que permitam avaliar o desempenho dos projetos de inovação de uma forma integrada continua a ser um obstáculo. O artigo começa por discutir os princípios do Six Sigma e do Balanced Scorecard para a avaliação do desempenho. Em seguida, são discutidas as vantagens do Six Sigma Business Scorecard como instrumento de suporte à avaliação do desempenho em projetos de inovação. Por último, são discutidas as vantagens do desenvolvimento no contexto de um ecossistema colaborativo. In the present context, companies to be competitive must develop high-performance innovation capabilities that enable them to respond quickly to market needs. However, the lack of tools and methodologies to assess the performance of innovation projects in an integrated way remains an obstacle. The article begins by discussing the principles of Six Sigma and the Balanced Scorecard for performance evaluation. Next, the advantages of the Six Sigma Business Scorecard are discussed as a tool to support the evaluation of performance in innovation projects. Finally, the advantages of development in the context of a collaborative ecosystem are discussed.
- Application of triz methodology to support the emergence of collaborative networksPublication . Navas, Helena; Abreu, António; Dias, AnaNowadays, companies operate in markets exposed to the effects of globalization, the opportunities for conducting business are becoming shorter in terms of time as well as the business environment is increasingly volatile. Thus, companies have to start learning to work together in certain areas or skills, to follow different paths other through the stimulation of inter-firm relationships giving rise to organizational models based on networks of collaboration between companies. However, a major challenge with the knowledge that this area faces is related to the need to develop a general theory of collaborative networks. Thus, the establishment of collaborative processes in response to a business opportunity should not follow an ad-hoc process, but instead must be supported by appropriate methodologies to support the process of analysis of technological and organizational systems, identify contradictions and problematic situations and process indicate the likely solution to the found problems. In this context, the Theory of Invention Problem Solving, better known by its acronym TRIZ, aims to aid in the detection of contradictions regarding systems and the generation of creative solutions which eliminate the contradictions found and get major improvements in technological and organizational systems. Innovation is crucial to increasing the efficiency of organizations, to improve competitiveness and profitability, since life cycle of products is becoming shorter. The collaborative chains need to develop innovative solutions progressively with the aim of improving processes. The TRIZ methodology can indicate some guidelines for managers of companies and their network since it The 2016 International Conference on Systematic Innovation July 20-22, 2016, Lisbon, Portugal allows to generate solutions to radical or based on the application of the latest scientific discoveries and experienced little change. The aim of this paper is to contribute to greater agility and sustainability of the processes of formation of collaborative chains to meet business opportunities, introducing the TRIZ methodology supporting the creation and development of collaborative chains.
- Avaliação do risco de inovação em ecossistemas colaborativos com base na lógica difusaPublication . Abreu, António; Moleiro Martins, José; Calado, João Manuel FerreiraAtualmente, as empresas no mercado global têm que alcançar altos níveis de desempenho e competitividade para se manterem "vivas." De acordo com vários autores e como é frequentemente referido em vários relatórios, uma das principais fontes de vantagem competitiva é a capacidade de inovação. A identificação e quantificação dos riscos de inovação existentes ou potenciais num ambiente colaborativo é um elemento importante para a ampla adoção do paradigma do ecossistema de inovação. No entanto, a falta de modelos que permitam analisar os riscos de inovação num ambiente colaborativo é uma limitação. De modo a abordar este problema, este artigo apresenta um modelo para analisar o nível de risco em projetos de co-inovação baseado numa avaliação qualitativa, incluindo uma base quantitativa, cujo o seu desenvolvimento foi suportado na aplicação da lógica difusa. Por último, com base nos resultados obtidos da aplicação do modelo a uma rede colaborativa Portuguesa, são apresentados e discutidos os benefícios e os desafios encontrados Nowadays, enterprises in global markets have to achieve high levels of performance and competitiveness to stay “alive" . According to several authors and as frequently mentioned by reports from practical case studies, one of the most relevant sources of competitive advantage is the innovation capacity. The identification and quantification of the existing or potential innovation risks in a collaborative environment, is an important element for the wide adoption of the innovation ecosystem paradigm. However, models to understand the innovation risks in a collaborative environment are lacking. In order to address this issue, this paper introduces an approach based on a qualitative assessment, including a quantitative basis, whose development was supported using fuzzy logic for analyzing the level of risk in co-innovation projects. Finally, based on experimental results from a Portuguese collaborative network, a discussion about the benefits and challenges found are presented and discussed.
- Control charts to support trust monitoring in dynamic logistics networksPublication . Abreu, António; Requeijo, José; Calado, João Manuel Ferreira; Dias, AnaNowadays, companies to be competitive must develop capabilities that enable them to respond quickly to market needs. According to some managers, the strategy is the development of dynamic logistics networks based on a collaborative environment. However, the absence of mechanisms to detect and even anticipate potential opportunistic behaviour is an obstacle to the proliferation of this way of working. The article aims to understand the role of trust to sustainability of collaborative processes. The paper begins by discussing the trust properties. It is then discussed how statistical control charts can be used to support the trust monitoring of each member within a collaborative ecosystem. The control charts’ tools suggested in this paper are the Z control charts for trust level monitoring and the Zi capacity index. Finally, it is discussed how this approach can be applied to dynamic logistics networks within the context of a collaborative ecosystem.
- Controlo Estatístico do Processo para Número Reduzido de DadosPublication . Requeijo, José; Matos, Ana Sofia; Abreu, AntónioEm alguns sistemas produtivos pretende-se controlar várias características da qualidade com um número restrito de dados, não sendo possível estimar convenientemente os parâmetros do processo (média e variância), impossibilitando a implementação do Controle Estatístico do Processo tradicional (SPC). Como resposta, sugere-se a adoção dos desenvolvimentos de Quesenberry, que consiste na transformação das estatísticas no instante i através dos parâmetros estimados no instante ( ) considerando-se todos os dados ocorridos até este instante. Este artigo aborda duas situações, o SPC univariado e multivariado, com a aplicação de estatísticas Q. Tanto a estatística Q univariada como a MQ multivariada são distribuídas segundo a distribuição Normal reduzida e assim, o controlo de cada característica pode ser representado num mesmo documento (carta de controlo). É sugerido a aplicação dos índices QI e QS para o estudo univariado da capacidade do processo, que são representados na respetiva carta de controlo Q. Assim é possível em tempo real avaliar o desempenho dos processos e prever a possibilidade de produzir produtos não conformes, aumentando a satisfação do cliente. A metodologia proposta é aplicável a diferentes sistemas produtivos (indústria e serviços). É apresentado um estudo de caso com recurso à metodologia proposta Some production systems control many quality characteristics with a restricted amount of data, not allowing a conveniente estimation of the process parameters (mean and variance), thereby creating a difficulty in implementing the traditional Statistical Process Control (SPC). In order to address this question, the approach suggested is to adopt the developments proposed by by Charles Quesenberry, which consists in the statistics sample transformation at time i. This transformation is based on parameter estimation at time (i – 1). This paper addresses two situations, the univariate and multivariate SPC, with the use of Q dimensionless statistics. Both univariate (Q) and multivariate (MQ) statistics are distributed according to standard Normal distribution. It is also suggested the application of new capability indices QL and QU to study the univariate process capability, which are represented in the mean Q control chart to evaluate in real time the performance of the various processes and predict the possibility of production of nonconforming product, which will increase customer satisfaction. The methodology is applicable to different production systems, both for industry and services. Based on a methodology developed, a case study is presented and discussed.