FE - Artigos de Revistas Internacionais com Arbitragem Científica

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    Inulinase from Rhodotorula mucilaginosa : immobilization and application in the production of fructooligosaccharides
    (The Korean Society of Food Science and Technology, 2021-07) de Araujo Ribeiro, Geise Camila; Fernandes, Pedro; Silva, Dayse Alessandra Almeida; Brandão, Hugo Neves; de Assis, Sandra Aparecida; Faculdade de Engenharia
    The crude extract containing inulinase from Rhodotorula mucilaginosa was obtained by submerged fermentation. Inulinase was immobilized on chicken eggshell by physical adsorption and covalent crosslinking, using glutaraldehyde as a crosslinking reagent, and Celite by adsorption. Fructooligosaccharides production was performed using immobilized inulinase (5%, w/v) and inulin substrate solution under experimental conditions evaluated through Doehlert experimental design. The production of inulinase was optimized for concentrations of D-glucose and yeast extract at 12.5 and 0.5 g/L, respectively, resulting in an optimal activity of 0.62 U. The optimal pH and temperature for enzyme activity were 8.0 and 75 °C, respectively, leading to an optimal activity of 3.54 U. The highest immobilization efficiency (46.27%) was obtained upon immobilization on Celite. Immobilization by adsorption to eggshell allowed for specific activity of 4.15 U/g, and adsorption to Celite resulted in specific activity of 3.70 U/g. The highest titer in fructooligosaccharides was obtained with an initial inulin concentration of 250 g/L (25%, w/v), and a reaction time of 16 h. Hence, immobilized inulinase proved to be a promising catalyst for fructooligosaccharides production since the formulation is performed through a simple, low-cost, and large-scale applicable methodology.
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    Comparing Freshman and doctoral engineering students in design : mapping with a descriptive framework
    (Taylor and Francis Ltd., 2017-11-02) Carmona Marques, P.; Faculdade de Engenharia
    This paper reports the results of a study of engineering students’ approaches to an open-ended design problem. To carry out this, sketches and interviews were collected from 9 freshmen (first year) and 10 doctoral engineering students, when they designed solutions for orange squeezers. Sketches and interviews were analysed and mapped with a descriptive ‘ideation framework’ (IF) of the design process, to document and compare their design creativity (Carmona Marques, P., A. Silva, E. Henriques, and C. Magee. 2014. “A Descriptive Framework of the Design Process from a Dual Cognitive Engineering Perspective.” International Journal of Design Creativity and Innovation 2 (3): 142–164). The results show that the designers worked in a manner largely consistent with the IF for generalisation and specialisation loops. Also, doctoral students produced more alternative solutions during the ideation process. In addition, compared to freshman, doctoral used the generalisation loop of the IF, working at higher levels of abstraction. The iterative nature of design is highlighted during this study–a potential contribution to decrease the gap between both groups in engineering education.
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    A descriptive framework of the design process from a dual cognitive-engineering perspective
    (Taylor and Francis, 2014) Marques, Pedro D.B.Carmona; Silva, Arlindo José P.F.; Henriques, Elsa M.P.; Magee, Christopher L.; Faculdade de Engenharia
    This article proposes a new descriptive framework, which we label as the “ideation framework” (IF), of the design process from a dual cognitive-engineering perspective, partly based on existing frameworks from both fields and previous work by the author. The framework is for the ideation or front-end phase of the product development process, representing the interface between cognitive psychology and engineering design. Three domains – inspiration, decomposition, and integration – and three spaces – problem-space, idea-space, and concept-space – are the elements of the framework. The iterative flow of the engineering design process passes through the three domains in a semi-controlled way, through a sequence of specialization and generalization process loops in and between the spaces. An empirical descriptive examination of the ideation process is performed using designers with limited design experience. The designers were faced with a design problem that they had to solve in a limited period of time. Their designs were analyzed, and a post-exercise interview was done to uncover each of the participants’ design process. The empirical work indicates these designers worked in a manner largely consistent with the IF.
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    A model for fostering creativity in the product development process
    (Taylor and Francis, 2021-02) Marques, Pedro Carmona; Faculdade de Engenharia
    The present paper illustrates a pilot experiment in which a new model for fostering creativity in the product development process is tested with novice engineers. After introducing creativity in the field of product development, the current author presents the new standard. The theoretical background that embodies the new model is presented, based on relevant literature. Making use of the new model, a methodology for testing it, using novice engineers is then proposed. It relies on the comparison between novices that were trained in the model in comparison to other novices that were not trained in the model. Higher results for creativity achieved by novice engineers that have employed the model show the advantages of its application during product development activities
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    Capacitação social – comunidades em território de risco
    (2018-04) Santos, Isabel Abreu dos; Vasconcelos, Lia Maldonado Teles de; Pires, Iva; Faculdade de Engenharia
    Vivemos numa sociedade em que os cidadãos enfrentam uma multiplicidade de riscos, de diversas naturezas e níveis de complexidade, e na qual a elevada ocorrência de acidentes afeta a estrutura social das comunidades, a saúde humana e o ambiente natural e edificado. Há uma crescente consciencialização da necessidade de dar resposta a estas situações. O principal desafio da investigação é o de verificar se a prática de exercícios à escala real, envolvendo autoridades, decisores, academia e as pessoas, permite uma melhor preparação para as ações individuais e coletivas de prevenção e atuação face à ocorrência de um desastre. A metodologia aplicada baseou-se na análise de estudos de caso, com observação e participação de quatro exercícios LIVEX, simulacros realizados à escala real, entre 2012 e 2015, numa comunidade portuguesa, localizada em território de risco. Os exercícios referiram-se a um cenário de risco tecnológico (acidente industrial) e três cenários de risco natural (sismo). A análise de resultados do estudo, permitiu testar a participação das populações, a utilização de equipamentos, e as relações institucionais de resposta à emergência (nomeadamente as comunicações). Possibilitou ainda inferir que a forma mais eficiente de aprender é pela experiência, no individual ou no coletivo. As conclusões permitem afirmar que a prática de realização de exercícios LIVEX contribuem para a construção de conhecimento, geração de confiança nas instituições e profissionais, na comunicação de ciência, levando ao empoderando das pessoas para tomarem as decisões mais acertadas em face de situações limite em que a sua vida e dos seus familiares se pode encontrar em perigo. Setúbal, pela prática continuada de modelos de participação ativa em exercícios à escala real, pode vir a constituir uma comunidade de prática, um exemplo tipo a ser replicado por outras comunidades.
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    Improvement of aglycone content in soy isoflavones extract by free and immobilized β-Glucosidase and their effects in lipid accumulation
    (Springer, 2020-11-01) Angelotti, Joelise A.F.; Dias, Fernanda F.G.; Sato, Hélia H.; Fernandes, Pedro; Nakajima, Vânia M.; Macedo, Juliana; Faculdade de Engenharia
    Soybean is one of the most important commodities in the world, being applied in feed crops and food, pharmaceutical industries in different ways. Soy is rich in isoflavones that in aglycone forms have exhibited significant anti-obesity and anti-lipogenic effects. Obesity is a global problem as several diseases have been related to this worldwide epidemic. The aim of this work was to verify the effect of free and immobilized β-glucosidase, testing Lentikats, and sol–gel as carriers. Moreover, we wanted to examine if the different types of hydrolysis would generate extracts with distinct biological activity concerning lipid accumulation, PPAR-α regulation, and TNF-α, IL-6, and IL-10 concentrations using in vitro assays. Our results show that all formulations of β-glucosidase could hydrolyze soy isoflavones. Thus, after 24 h of incubation, daidzein content increased 2.6-, 10.8-, and 12.2-fold; and genistein content increased 11.7, 11.4, and 11.4 times with the use of free enzyme, Lentikats®, and sol–gel immobilized enzyme, respectively. Moreover, both methodologies for enzyme immobilization led to promising forms of biocatalysts for application in the production of soy extracts rich in isoflavones aglycones, which are expected to bring about health benefits. A mild lipogenic effect was observed for some concentrations of extracts, as well as a slight inhibition in PPAR-α expression, although no significant differences were noticeable in the cytokines TNF-α, IL-10, and IL-6 as compared with the control.
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    Production, characterization, and immobilization of protease from the yeast Rhodotorula oryzicola
    (Wiley-Blackwell, 2021-10) de Oliveira, Juliana Mota; Fernandes, Pedro; Benevides, Raquel Guimarães; de Assis, Sandra Aparecida; Faculdade de Engenharia
    The protease was produced extracellularly in submerged fermentation by the yeast Rhodotorula oryzicola using different sources of nitrogen and maximum activity (6.54 × 10−3 U/mg) was obtained in medium containing 2% casein (w/v). Purification of the protease by gel filtration chromatography resulted in a 3.07-fold increase of specific protease activity. The optimal pH and temperature for enzyme activity were 6.51 and 63.04 °C, respectively. Incubation in the presence of some salts enhanced enzyme activity, which peaked under 0.01 M BaCl2. The enzyme retained about 90% of enzymatic activity at temperatures 50–60 °C. The commercially available enzyme carriers evaluated, silica gel, Celite 545, and chitosan effectively immobilized the protease. The enzyme immobilized in Celite 545 retained 73.53% of the initial activity after 15 reuse cycles. These results are quite promising for large-scale production and immobilization of protease from R. oryzicola, as the high operational stability of the immobilized enzyme lowers production costs in biotechnological applications that require high enzymatic activity and stability under high temperatures.
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    Building sustainable creativity : a conceptual framework
    (European Center of Sustainable Development, 2016) Marques, Pedro Carmona; Faculdade de Engenharia; RCM2+ - Centro de Investigação em Gestão de Ativos e Engenharia de Sistemas
    Climate change, limited energy resources and population growth raise questions about sustainability and decisions for future generations. There is a need to contribute to a more sustainable world. This can be achieved with the use of creativity in, for example, product lifecycle management. Built on the literature about creativity and sustainability, a conceptual framework of sustainable creativity is proposed on the integration of the fields. The proposed framework is an attempt to the creation of sustainable concepts and includes the domains of “decomposition” and “integration” where the problem-, idea-, and concept-space are built on. Feedback loops are analysed and discussed as an important part of any radical/incremental product/service development within lifecycle management activities.
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    Integrating Product-Service Systems with New Business Models Definition for Manufacturing Industries
    (IGI Global Publishing, 2014) Marques, Pedro C.; Cunha, Pedro F.; Faculdade de Engenharia; RCM2+ - Centro de Investigação em Gestão de Ativos e Engenharia de Sistemas
    Nowadays, manufacturing companies are pressured to be competitive and innovative. Particularly this concerns the delivery of value to their customers. The assessment of the overall value chain, designed and implemented for a specific product and/or service, should be sustained by new business models (NBM), thus contributing to higher levels of customer satisfaction. Integrated product-services are assuming importance, allowing manufacturing companies to achieve longer and stable relationships with their customers. This requires, among other, organizational changes and novel methodologies for product-service development. In fact, an effective integration allows product-service innovation, which being exploited, contributes significantly to businesses' competitiveness and sustainability. In this paper, a "roadmap" for NBM definition and implementation is presented, along with a new methodology for Product-Service Systems (PSS) development. Two case studies are used to test both the roadmap and the PSS methodology. As such, this work is expected to contribute to a clear understanding of NBM and their integration in a methodology for PSS.
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    Uavnoma : a UAV-NOMA Network Model under non-ideal conditions
    (Ubiquity Press, 2022-10-19) Lima, Brena; Fachada, Nuno; Dinis, Rui; Costa, Daniel B.; Beko, Marko; COPELABS (FCT) - Centro de Investigação em Computação Centrada nas Pessoas e Cognição (CTS)
    Uavnoma is a set of Python functions and a front-end script for modeling, studying, and analyzing the communication system composed by an unmanned aerial vehicle (UAV) and two ground users. We assume that the UAV acts as an aerial base station to serve the users according to non-orthogonal multiple access (NOMA) principles. For more practical insights, residual hardware impairments (RHI) and imperfect successive interference cancellation (ipSIC) are considered. More specifically, uavnoma allows the modelers to study and visualize the system performance in terms of achievable rate and outage probability. Additionally, the package produces figures and tables showcasing results from the specified performance metrics. KEYWORDS: Non-orthogonal multiple access (NOMA); Non-ideal conditions; Numerical simulation; Performance analysis; Unmanned aerial vehicle (UAV)
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    Mycobacterium vaccae adaptation to disinfectants and hand sanitisers, and evaluation of cross-tolerance with antimicrobials
    (Multidisciplinary Digital Publishing Institute (MDPI), 2020-09) de Carvalho, Carla C.C.R.; Teixeira, Raquel; Fernandes, Pedro; Faculdade de Engenharia
    Mycobacterium vaccae is being considered as an adjuvant to antituberculosis therapy, tested for the treatment of autoimmune diseases, and as an anti-depressive agent. This bacterium is ubiquitous in the environment and the widespread use of disinfectants and sanitisers may lead to its adaptation to these compounds. In the present study, M. vaccae cells adapted to these compounds mainly by making adjustments in their lipid composition and net surface charge. The modifications in the lipid composition led to changes in membrane permeability which resulted in increased tolerance towards levofloxacin, thioridazine, and omeprazole.
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    Enlarged PLIN5-uncoated lipid droplets in inner regions of skeletal muscle type II fibers associate with type 2 diabetes
    (Elsevier GmbH, 2022-04) Fachada, Vasco; Rahkila, Paavo; Fachada, Nuno; Turpeinen, Tuomas; Kujala, Urho M.; Kainulainen, Heikki; COPELABS (FCT) - Centro de Investigação em Computação Centrada nas Pessoas e Cognição (CTS)
    Skeletal muscle physiology remains of paramount importance in understanding insulin resistance. Due to its high lipid turnover rates, regulation of intramyocellular lipid droplets (LDs) is a key factor. Perilipin 5 (PLIN5) is one of the most critical agents in such regulation, being often referred as a protector against lipotoxicity and consequent skeletal muscle insulin resistance. We examined area fraction, size, subcellular localization and PLIN5 association of LDs in two fiber types of type 2 diabetic (T2D), obese (OB) and healthy (HC) individuals by means of fluorescence microscopy and image analysis. We found that T2D type II fibers have a significant sub-population of large and internalized LDs, uncoated by PLIN5. Based on this novel result, additional hypotheses for the pathophysiology of skeletal muscle insulin resistance are formulated, together with future research directions.
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    O contributo da igualdade de género para as operações na Guarda Nacional Republicana
    (Associacao Iberica de Sistemas e Tecnologias de Informacao, 2023-10) Malheiro, Luís Carlos Rodrigues; Bessa, Fernando José da Conceição; Reis, João Carlos Gonçalves Dos; Saraiva, Luís Eduardo; Faculdade de Engenharia
    O presente estudo foi conduzido com o foco de: analisar o contributo da igualdade de género para o sucesso das operações na Guarda Nacional Republicana (GNR). Baseado em um raciocino indutivo, com uma estratégia predominantemente qualitativa e um desenho de estudo de caso, foi recolhida informação com recurso a entrevistas semiestruturadas junto de dez decisores com experiência na área das operações da GNR. Após recolha e tratamento da informação primária, tendo por base o método comparado, foi possível confirmar, em outras realidades/latitudes, algumas tendências que emergiram na revisão da literatura. O caminho desenvolvido permite avançar que: (1) a perspetiva de género ainda não é incorporada no planeamento das operações da GNR; (2) o processo de integração das mulheres ainda não está concluído sendo necessário recrutar mais mulheres; (3) existem decisores ligados às operações da GNR que concordam com limitações às tarefas/missões operacionais a realizar por/pelas mulheres; (4) a principal limitação identificada sobre a inclusão de mulheres nas operações está ligada à logística e; (5) era importante ter mais mulheres para otimizar as operações da GNR, sobretudo para missões e tarefas como revistas a mulheres e o projeto Investigação e Apoio a Vítimas Específicas.
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    Politics, power, and influence : defense industries in the post-cold war
    (Multidisciplinary Digital Publishing Institute (MDPI), 2021-01) Dos Reis, João Carlos Gonçalves; RCM2+ - Centro de Investigação em Gestão de Ativos e Engenharia de Sistemas
    The post-Cold War era is placing the defense industry at a crossroads. If, on the one hand, it is under great pressure to guarantee warlike efforts around the world, with tight budgets and uncertain lead-times, on the other hand, it is seen as a central instrument for national sovereignty and foreign policy. The purpose of this research is to report the state-of-the-art of the existing literature and explore the most relevant research areas in order to provide the conceptual basis for further empirical research. To do so, this study uses a preferred reporting items for systematic review and meta-analysis (PRISMA), which is an adequate technique as it allows one to discover concepts, ideas, and debates about the defense industry. The results evidenced three different approaches to the defense industry—integration, autarky, and domination. In that regard, we present several case studies in which the defense industry is used as an instrument of foreign policy or national sovereignty. Future studies may focus on empirical research to validate the theoretical findings or to identify variables that lead some defense industries to seek synergies, resorting to mergers and acquisitions, while other defense companies prefer to obtain State funds.
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    A igualdade de género na União Europeia : a implementação da agenda mulheres, paz e segurança
    (Associacao Iberica de Sistemas e Tecnologias de Informacao, 2022-04) Malheiro, Luís; Menezes, Sofia; Reis, João; Machado, Paulo; Romão, Ana; Bessa, Fernando; RCM2+ - Centro de Investigação em Gestão de Ativos e Engenharia de Sistemas
    A presente investigação versa sobre a promoção da igualdade de género conceitos estruturantes que permitiram desenhar o modelo analítico criado para dar espectro da segurança da União Europeia, que apresentam diversos níveis de de implementação da agenda, ao nível institucional, para promoção da mudança sendo crucial: explicitar a igualdade nos documentos internos e nos objetivos para o dirigente máximo; estabelecer regras sobre o respeito pela dignidade das mulheres e dos homens no local de trabalho; incluir a perspetiva de género no orçamento e alocar verbas; estabelecer o princípio da não discriminação e a promoção da os direitos e deveres dos trabalhadores sobre igualdade e não discriminação; planeamento estratégico; e delinear e levar a cabo um plano para implementar a agenda.
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    Multi-enzyme systems in flow chemistry
    (Multidisciplinary Digital Publishing Institute (MDPI), 2021) Fernandes, Pedro; de Carvalho, Carla C.C.R.; Faculdade de Engenharia
    Recent years have witnessed a growing interest in the use of biocatalysts in flow reactors. This merging combines the high selectivity and mild operation conditions typical of biocatalysis with enhanced mass transfer and resource efficiency associated to flow chemistry. Additionally, it provides a sound environment to emulate Nature by mimicking metabolic pathways in living cells and to produce goods through the systematic organization of enzymes towards efficient cascade reactions. Moreover, by enabling the combination of enzymes from different hosts, this approach paves the way for novel pathways. The present review aims to present recent developments within the scope of flow chemistry involving multi-enzymatic cascade reactions. The types of reactors used are briefly addressed. Immobilization methodologies and strategies for the application of the immobilized biocatalysts are presented and discussed. Key aspects related to the use of whole cells in flow chemistry are presented. The combination of chemocatalysis and biocatalysis is also addressed and relevant aspects are highlighted. Challenges faced in the transition from microscale to industrial scale are presented and discussed
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    Defence industries and open innovation : ways to increase military capabilities of the Portuguese ground forces
    (Routledge, 2022) Reis, João; Melão, Nuno; Costa, Joana; Pernica, Bohuslav; RCM2+ - Centro de Investigação em Gestão de Ativos e Engenharia de Sistemas
    The European Defence Industry is undergoing profound changes. Industrial activity is now operating on a quintuple helix innovation model with the deep involvement of universities and governments in innovation. In addition, military innovations are being transferred to civil society, with increasing attention paid to the environment. In the first stage, we report on the state-of-the-art of existing research using PRISMA protocol. The PRISMA technique is widely accepted by the academic community for its ability to discover concepts, ideas, and debates about the defence industry. In the second stage, we present a case study involving the Portuguese Defence Industry, for which multiple data collection sources were used to ensure triangulation and corroboration. The results show that, in the light of the quintuple helix innovation model, it was possible to bring applications from theoretical discussion to real life. Moreover, within the scope of the triple helix, it was possible to develop, produce and test military products, allowing to improve the military capacity of ground forces. In the future, ecological concerns will likely increase, so we suggest a greater focus on this area of research. KEYWORDS : Defence industry; open innovation; ground military forces; quintuple helix
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    Digital transformation : a meta-review and guidelines for future research
    (Elsevier Ltd., 2023-01) Reis, João; Melão, Nuno; RCM2+ - Centro de Investigação em Gestão de Ativos e Engenharia de Sistemas
    The emergence of digital transformation has changed the business landscape for the foreseeable future. As scholars advance their understanding and digital transformation begins to gain maturity, it becomes necessary to develop a synthesis to create solid foundations. To do so, significant steps need to be taken to critically, rigorously, and transparently examine the existing literature. Therefore, this article uses a meta-review with the support of the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) Protocol. As a result, we identified six dimensions and seventeen categories related to digital transformation. The organizational, technological, and social dimensions are still pivotal in digital transformation, while two new dimensions (sustainability and smart cities) still need to be explored in the existing literature. The need to deepen knowledge in digital transformation and refine the dimensions found is of paramount importance, as it involves some complexity due to organizational dynamics and the development of new technologies. It was also possible to identify opportunities, challenges, and future directions.
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    Revisão sistemática da literatura sobre viés de género e aprendizagem máquina na segurança
    (Associacao Iberica de Sistemas e Tecnologias de Informacao, 2023-10) Malheiro, Luís Carlos Rodrigues; Bessa, Fernando José da Conceição; Reis, João Carlos Gonçalves Dos; Saraiva, Luís Eduardo; Faculdade de Engenharia
    O presente estudo foi desenvolvido com o propósito de: analisar os desafios da utilização de dados com viés de género para a aprendizagem da máquina na segurança. A procura das limitações da aprendizagem máquina e o debate sobre o contágio por via de dados desequilibrados na fase do treino, nomeadamente na dimensão do género, foi baseado no protocolo Prisma. Depois de serem definidas as palavras-chave a procurar e os critérios de exclusão, a densificação da análise das 39 investigações selecionadas foi promovida por via da utilização do VOSviewer, do Connected papers e do Treecloud. A conjugação das técnicas e procedimentos anteriores possibilitou concluir que: (1) os vieses cognitivos podem existir na aprendizagem máquina devido ao recurso a dados desequilibrados para treino; (2) proporcionar um treino com dados equilibrados (também sobre o género) a uma rede aumenta a sua resiliência; (3) é possível introduzir algoritmos com atributos gender sensitive para mitigar vieses na aprendizagem máquina; (4) existe um gap sobre investigações científicas relativamente a vieses de género no campo da segurança.
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    Economic disposal quantity of leftovers kept in storage : a Monte Carlo simulation method
    (De Gruyter Open Access, 2019) Assis, R.; Marques, Pedro Carmona; Santos, J. Oliveira; Vidal, R.; FE ¿ Faculty of Engineering
    This article describes how to reach an item's threshold, or in other words, the limit time for it to be retrieved from stock and sold for a different use, as well as the remaining foreseen period for this situation to occur. Once a minimum length, or weight, is reached, left quantities are more difficult to sell, as demand often exceeds the remaining parts or leftovers. The number of unfulfilled orders increases, as time goes by, until it becomes further cost effective to dispose the leftover and sell it for a lower price and alternative use. A Monte Carlo simulation model was built in order to consider the randomness of future transactions and quantifying consequences providing this way a simple and effective decision-making framework.