Reframing the selection of hydraulic turbines integrating analytical hierarchy process (AHP) and fuzzy VIKOR multi-criteria methods

Before selecting a proper hydraulic turbine for power generation, conflicting factors frequently emerge from the wide range of available technology alternatives. The preliminary selection of hydraulic turbines (PSHT) has been usually carried out by overlooking and/or overshadowing downstream and upstream processes. The development of a new conceptual framework that allows for including more parameters into the decision-making process at company levels is still required to avoid the danger of engaging in a one-dimensional approach, which would not only result in a reduced and simplistic vision of the choice but would also overlook the trade-offs between individual aspects and the possible unintended side-effects. This paper aims to provide empirical evidence for the PSHT by proposing a well-thought-out framework based on a mixed methodology approach (analytical hierarchy process (AHP) and fuzzy-VIKOR multi-criteria methods) and focused on small hydropower projects. A total of 16 criteria are proposed and divided into 4 main categories—(i) turbine performance, (ii) turbine and generator costs, (iii) other equipment costs, and (iv) civil costs. Findings reported here reveal a specific alignment between investors’ preferences and experts’ judgments with real market practices. The 16 proposed criteria can be further considered to support the decision-making process for PSHT in different head and flow conditions.This work has been supported by FCT – Fundação para a Ciência e Tecnologia within the R&D Units Project Scope: UIDB/00319/2020

Ferramenta para avaliação dos aspectos da ergonomia e princípios lean em pequenas e médias empresas

Several studies discuss the relationships between ergonomics and Lean principles, seeking to investigate their synergies and conflicts. This paper analyzes these relationships through a review of related studies in order to list the evaluable aspects of both areas. In order to systematize this review, we used the analytical (to extract the evaluable aspects), and the interpretative techniques (in order to discuss the relation through the combination of these aspects). The aspects were confronted and discussed their relations, where 51% were interpreted as harmonious, 37% partially harmonious and 12% of the relations (2x) were considered conflicting. From these aspects, a tool was created to evaluate ergonomics and Lean principles in small companies, where such practices are not formalized. A pilot test of the questionnaire was carried out in the company of plywood, whose results showed aspects of ergonomics and lean production that should be improved, such as the adequacy of work organization, environmental conditions (temperature and noise), production layout, encouraging employee participation in solutions and ergonomics in office environments. The Pearson coefficient indicated the correlations between the aspects, noting that maintaining adequate demand contributes to the reduction of waste, that prevention and health practices maximize productivity, and yet that system and worker performance are positively related. These results differ from the interpretative analysis, since the first one was carried out from the discussions contained in the articles, and the second presents a diagnosis of a specific environment. The correlation analysis can be used by the manager in order to understand the relationship of the aspects perceived in his company and to base strategies. It is concluded that this tool is helpful to identify ergonomic and Lean demands, and can contribute to environments that seek harmony between ergonomics and lean production.Diversos estudos recentes discutem as relações da ergonomia e os princípios Lean, procurando investigar as sinergias e conflitos entre ambas as áreas. Este artigo analisa essas relações por meio de uma revisão de literatura desses estudos, a fim de elencar os aspectos avaliáveis dessa relação. No intuito de sistematizar essa revisão, utilizou-se a técnica analítica (para extrair os aspectos avaliáveis), e a interpretativa (a fim de discutir a relação através da combinação desses aspectos). A partir desses aspectos, criou-se uma ferramenta para avaliar a ergonomia e o sistema Lean a partir dos aspectos identificados. Os aspectos foram combinados e discutidas as suas relações, onde 51% das relações foram harmoniosas, 37% parcialmente harmoniosas e 12% das relações foram consideradas conflitantes. Aplicou-se teste piloto do questionário em empresa de compensados, cujos resultados mostraram aspectos da ergonomia e da produção enxuta que devem ser melhorados, tais como adequação da organização do trabalho, das condições ambientais (temperatura e ruído), do layout de produção, incentivo a participação dos trabalhadores nas soluções e ergonomia nos ambientes de escritório. Conclui-se que esta ferramenta é útil para identificar as demandas ergonômicas e Lean, podendo contribuir para os ambientes que buscam harmonia entre a ergonomia e a produção enxuta

Gerenciamento de projetos

Gerenciamento de Projetos desmistifica a ideia de que a gestão de projetos é comum apenas nas grandes organizações. Micro, pequenas e médias empresas podem e devem se beneficiar das técnicas e ferramentas dessa prática gerencial e aplicá-las na inovação de seus produtos, serviços ou processos. A adoção do gerenciamento de projetos pode colocar a empresa em patamares diferenciados em relação a seus concorrentes, garantindo a sua fixação no mercado

Método multicriterial para seleção de processos de fundição de metais

O objetivo principal da tese foi desenvolver um método multicriterial de seleção de processos de fundição de metais (MMSPF) para fabricação de componentes, considerando-se critérios técnicos, ambientais e econômicos para ser aplicado nas fases iniciais do desenvolvimento do componente. O MMSPF é constituído pelos módulos de seleção técnica e econômica. O módulo de seleção técnica é destinado a antecipar as atividades de seleção de processos, a serem desenvolvidas na fase de projeto preliminar, enquanto o módulo de seleção econômica é destinado a antecipar as atividades de seleção de processos, necessárias à fase de projeto detalhado. O MMSPF realiza a seleção de processos de forma sequencial. Inicialmente, avaliando aspectos técnicos e, posteriormente, considerando aspectos econômicos. O MMSPF contempla as seis classes de ligas metálicas mais utilizadas na produção de componentes fundidos: aços, ferros fundidos, ligas de alumínio, ligas de cobre, ligas de magnésio e ligas de zinco, apropriadas aos processos de fundição de metais destinados à produção de peças. O MMSPF contempla os quinze principais processos de fundição de metais destinados a produção de peças: areia verde – manual (P1), areia verde – mecanizada (P2), areia verde – automatizada (P3), areia silicato - CO2 (P4), areia com resina – cura frio (P5), areia com resina – shell molding (P6), processo molde de gesso – plaster molding (P7), processo molde cerâmico (P8), investment casting (P9), molde cheio - lost foam (P10), fundição centrífuga - molde metálico (P11), molde permanente – gravidade (P12), molde permanente - baixa pressão (P13), fundição sob pressão - die casting (P14) e squeeze casting (P15) como conjunto solução da seleção. As inovações propostas pelo MMSPF foram: (i) consolidação das diferentes fontes de informação dos processos a serem utilizadas no MMSPF, por meio de uma função de agregação; (ii) utilização de aspectos ambientais como critérios para seleção de processos de fundição de metais; (iii) consideração da estimação de custos de fabricação para realizar a seleção de processos de fundição de metais a partir de um índice de custo de fabricação, relativo ao desempenho técnico. Também foi desenvolvido um aplicativo computacional para implementar o MMSPF composto por três elementos principais: um software de planilha eletrônica (Microsoft Excel), no qual são realizadas todas as operações matemáticas necessárias ao desenvolvimento das etapas operacionais do MMSPF; um banco de dados, o software livre SQLite, responsável por armazenar as informações utilizadas no aplicativo computacional do MMSPF; e a interface gráfica do usuário, que atua como elemento de conexão entre o banco de dados, o software de planilha eletrônica e o usuário.The main objective of this thesis was to develop a Multi-criteria Method for metal Casting Process Selection (MMCPS) to manufacturing components, considering technical criteria, environmental and economic to be applied in the early stages of design of the component. The MMCPS consists modules for the technical and economic selection. The technique selection module is designed to anticipate the activities of processes selection to be developed in the embodiment design, while the economic selection module is designed to anticipate selection process activities, necessary the detailed design phase. The MMCPS conducts the selection process sequentially. Initially, evaluating technical aspects and, subsequently, considering economic aspects. The MMCPS includes the six classes of metal alloys more used in the production of cast components: steel, cast iron, aluminum alloys, copper alloys, magnesium alloys and zinc alloys, suitable for metal shape casting processes. The MMCPS covers the fifteen main metal shape casting processes: green sand – hand molding (P1), green sand – mechanized molding (P2), green sand - automatic molding (P3), silicate-CO2 (P4), air-set/nobake (P5), shell molding (P6), plaster molding (P7), ceramic mold (P8), investment casting (P9), lost foam (P10), centrifugal casting – metallic mold (P11), permanent mold-gravity (P12), permanent mold-low pressure (P13), die casting (P14) and squeeze casting (P15) as the set solution for the selection process. The innovations proposed by MMCPS were: (i) consolidation of different sources of information processes to be used in MMCPS through an aggregation function; (ii) use of environmental aspects as criteria for selection of metal casting processes; (iii) consideration of the cost estimation of manufacturing to make the metal casting process selection from an index of manufacturing cost on the technical performance. Also developed a computational tool to implement the MMCPS composed of three main elements: a spreadsheet software (Microsoft Excel), which are held every mathematical operations necessary for the development of operational steps MMCPS; a database, freeware SQLite, responsible for storing information used in the application of computational MMCPS, and the graphical user interface, which acts as a link between the database, the spreadsheet software and the user

Lean and Green Product Development in SMEs: A Comparative Study between Small- and Medium-Sized Brazilian and Japanese Enterprises

Facing the new challenges in production processes, companies should adopt lean and green practices in product development. In SMEs, the application of these practices is more complex. This work explores the maturity of lean–green methodologies in the product development process in Brazilian and Japanese SMEs. The methodology used is multicriteria, combining the analytic hierarchy process (AHP) and TOPSIS 2-tuple method, applied to four Japanese SMEs and four Brazilian SMEs in the metalworking sector. The criteria for evaluating SMEs are company flexibility, difficulties with NPD, innovation, limited resources, and personnel authority high. The TOPSIS method alternatives refer to 18 lean–green enablers. In the AHP method, the prioritisation of criteria between Japanese and Brazilian specialists presented divergences. In the Japanese context, the incidence of innovation is predominant, while in the Brazilian context, the most important is the limited resources. In the TOPSIS 2-tuple method, the results showed a higher level of maturity in lean–green methodologies in Japanese companies than in Brazilian ones. Lean practices are more evolved compared to sustainable practices in both countries. The study also addressed how open innovation adoption may contribute to innovation and NPD practices. Policymakers need to understand the heterogeneity of innovators within SMEs and how they differently innovate, developing distinct internal and external activities