FE - Artigos de Revistas Internacionais com Arbitragem Científica

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Defence industries and open innovation: ways to increase military capabilities of the Portuguese ground forces
(Edições Universitárias Lusófonas, 2022) Reis, ‪João Carlos Gonçalves dos; Melão, Nuno; Costa, Joana; Pernica, Bohuslav; Faculdade de Engenharia
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
Uavnoma: A UAV-NOMA Network Model under Non-Ideal Conditions
(Edições Universitárias Lusófonas, 2022-10-17) Lima, Brena; Fachada, Nuno; Dinis, Rui; Costa, Daniel Benevides da; Beko, Marko; Faculdade de Engenharia
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)
Generating multidimensional clusters with support lines
(Elsevier, 2023) Fachada, Nuno; de Andrade, Diogo; Faculdade de Engenharia
Synthetic data is essential for assessing clustering techniques, complementing and extending real data, and allowing for more complete coverage of a given problem’s space. In turn, synthetic data generators have the potential of creating vast amounts of data – a crucial activity when real-world data is at premium – while providing a well-understood generation procedure and an interpretable instrument for methodically investigating cluster analysis algorithms. Here, we present Clugen, a modular procedure for synthetic data generation, capable of creating multidimensional clusters supported by line segments using arbitrary distributions. Clugen is open source, comprehensively unit tested and documented, and is available for the Python, R, Julia, and MATLAB/Octave ecosystems. We demonstrate that our proposal can produce rich and varied results in various dimensions, is fit for use in the assessment of clustering algorithms, and has the potential to be a widely used framework in diverse clustering-related research tasks. Keywords: Synthetic data, Clustering, Data generation, Multidimensional data
Enlarged PLIN5-uncoated lipid droplets in inner regions of skeletal muscle type II fibers associate with type 2 diabetes
(Edições Universitárias Lusófonas, 2022-02) Fachada, Vasco; Rahkila, Paavo; Fachada, Nuno; Turpeinen, Tuomas; Kujala, Urho M.; Kainulainen, Heikki; Faculdade de Engenharia
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. Keywords: Lipid droplets, PLIN5, Type II diabetes, Skeletal muscle, Insulin resistance, Fiber type
Impact of artificial intelligence research on politics of the European Union member states : the case study of Portugal
(Edições Universitárias Lusófonas, 2020-08) Reis, João Carlos Gonçalves dos; Espírito Santo, Paula do; Melão, Nuno; Faculdade de Engenharia
Currently, artificial intelligence (AI) is at the center of academic and public debate. However, its implications on politics remain little understood. To understand the impact of the AI phenomenon on politics of the European Union (EU), we have carried out qualitative multimethod research by performing a systematic literature review and a case study. The first method was performed according to the preferred reporting items for systematic reviews and meta-analyses (PRISMA), in order to report the state-of-the-art in the existing literature and explore the most relevant research areas. The second method contained contributions from experts in data science and AI of the Portuguese scientific community. The results showed that solutions such as intelligent decision support systems are improving the political decision-making process and impacting the Portuguese society at local, regional, and national levels. We also found that practitioners and scientists are currently shifting their interests from environmental and biological sciences to healthcare services, which is bringing new challenges in terms of protecting patient/citizen data and growing concerns about handling of critical information. Future research may focus on comparative studies with other EU States to obtain a comprehensive and holistic understanding of the AI phenomenon.
Multi-enzyme systems in flow chemistry
(Edições Universitárias Lusófonas, 2021) Fernandes, Pedro Carlos de Barros; Carvalho, Carla C. C. R. de; 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
Where are smart cities heading? A meta-review and guidelines for future research
(Edições Universitárias Lusófonas, 2022) Reis, João Carlos Gonçalves dos; Marques, Pedro Alexandre; Marques, Pedro Carmona; Faculdade de Engenharia
(1) Background: Smart cities have been gaining attention in the community, both among researchers and professionals. Although this field of study is gaining some maturity, no academic manuscript yet offers a unique holistic view of the phenomenon. In fact, the existing systematic reviews make it possible to gather solid and relevant knowledge, but still dispersed; (2) Method: through a meta-review it was possible to provide a set of data, which allows the dissemination of the main theoretical and managerial contributions to enthusiasts and critics of the area; (3) Results: this research identified the most relevant topics for smart cities, namely, smart city dimensions, digital transformation, sustainability and resilience. In addition, this research emphasizes that the natural sciences have dominated scientific production, with greater attention being paid to megacities of developed nations. Recent empirical research also suggests that it is crucial to overcome key cybersecurity and privacy challenges in smart cities; (4) Conclusions: research on smart cities can be performed as multidisciplinary studies of small and medium-sized cities in developed or underdeveloped countries. Furthermore, future research should highlight the role played by cybersecurity in the development of smart cities and analyze the impact of smart city development on the link between the city and its stakeholders.
Politics, power, and influence : defense industries in the Post-Cold War
(Edições Universitárias Lusófonas, 2021-01) Reis, João Carlos Gonçalves dos; Faculdade de Engenharia
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.
Building sustainable creativity: a conceptual framework
(Edições Universitárias Lusófonas, 2019) Marques, Pedro Carmona; Faculdade de Engenharia
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.
Improvement of Aglycone Content in Soy Isoflavones Extract by Free and Immobilized β-Glucosidase and Their Effects in Lipid Accumulation
(Edições Universitárias Lusófonas, 2020-06) Angelotti, Joelise; Dias, Fernanda; Sato, Hélia; Fernandes, Pedro Carlos de Barros; Nakajima, Vânia; 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.
A igualdade de género na União Europeia: a implementação da agenda mulheres, paz e segurança
(Edições Universitárias Lusófonas, 2022) Malheiro, Luís Carlos Rodrigues; Menezes, Elisabete Sofia Nabais de Oliveira de Freitas e; Reis, João Carlos Gonçalves dos; Machado, Paulo Daniel Duarte; Romão, Ana Maria Carapelho; Bessa, Fernando José da Conceição; Faculdade de Engenharia
A presente investigação versa sobre a promoção da igualdade de género nas organizações de segurança da União Europeia. Face à aprendizagem decorrente das ações dos vinte anos da implementação da agenda mulheres, paz e segurança que enfatizam os desafios que subsistem na sua adoção, surgiu a questão que guiou o presente estudo: que fatores influenciam a implementação da agenda mulheres, paz e segurança na União Europeia? O estudo foi materializado na análise dos conceitos estruturantes que permitiram desenhar o modelo analítico criado para dar resposta à lacuna identificada. Em seguida, o estudo foi reforçado pela comparação dos resultados da mensuração de fatores, recolhidos junto de organizações do espectro da segurança da União Europeia, que apresentam diversos níveis de implementação da agenda. A investigação permitiu sublinhar a importância da fase 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 igualdade nos planos de formação, promovendo a realização de formações; divulgar os direitos e deveres dos trabalhadores sobre igualdade e não discriminação; fomentar políticas sectoriais que reforcem a igualdade; enfatizar a igualdade no planeamento estratégico; e delinear e levar a cabo um plano para implementar a agenda.
Mycobacterium vaccae adaptation to disinfectants and hand sanitisers, and evaluation of cross-tolerance with antimicrobials
(Edições Universitárias Lusófonas, 2020) Carvalho, Carla C. C. R. de; Teixeira, Raquel; Fernandes, Pedro Carlos de Barros; 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.
Upgrading end-of-line residues of the red seaweed Gelidium sesquipedale to polyhydroxyalkanoates using Halomonas boliviensis
(Edições Universitárias Lusófonas, 2020-09) Tuna, Stepan; Izaguirre, Jon; Bondar, Marina; Marques, Mafalda; Fernandes, Pedro Carlos de Barros; Fonseca, Maria Manuela Regalo da; Cesário, Maria; Faculdade de Engenharia
Agar extraction from Gelidium and Gracilaria red seaweed species produces hundred thousand ton of carbohydrate-rich residues annually. Gelidium sesquipedale waste biomass obtained after agar extraction, still contained 44.2 % w/w total carbohydrates (dry-weight basis). These residues were biologically up-graded to poly-3-hydroxybutyrate (P3HB) after saccharification of their carbohydrate fraction to simple sugars. A combined hydrolysis treatment using sulfamic acid followed by enzymatic hydrolysis with cellulases produced a glucose-rich hydrolysate with a negligible content of inhibitors. With this treatment a sugar yield of circa 30 % (g glucose/g biomass) was attained. The algal hydrolysates were assessed as carbon source for the production of P3HB by the halotolerant bacteria Halomonas boliviensis. A cell concentration of 8.3 g L−1 containing 41 % (w/w) of polymer and a yield (YP/S) of 0.16 gpolymer/gglucose were attained in shake flask assays. In this work, cellulose-rich seaweed waste was shown to be an upgradable, sustainable source of carbohydrates.
Economic disposal quantity of leftovers kept in storage : a monte carlo simulation method
(De Gruyter Open Access, 2019) Marques, Pedro Carmona; Assis, R.; Vidal, R.; Santos, J. Oliveira; Faculdade de Engenharia
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.
Inulinase from Rhodotorula mucilaginosa: immobilization and application in the production of fructooligosaccharides
(Edições Universitárias Lusófonas, 2021) Ribeiro, Geise Camila de Araújo; Fernandes, Pedro Carlos de Barros; Silva, Dayse Alessandra Almeida; Brandão, Hugo Neves; Assis, Sandra Aparecida de; 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.
Economic disposal quantity of leftovers kept in storage: a Monte Carlo simulation method
(Edições Universitárias Lusófonas, 2019) Assis, Rui; Marques, Pedro Carmona; Santos, José Oliveira; Vidal, Raphaela; Faculdade de Engenharia
This article describes how to reach an item’s threshold, or in other words, the limit time for it to be re 5 trieved 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 quan tities are more difficult to sell, as demand often exceeds the remaining parts or leftovers. The number of unfulfilled 10 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 15 way a simple and effective decision-making. KEYWORDS: Decision-making ; Economical Optimization ; Monte-Carlo Simulation ; Stochastic Process
Procedural generation of 3D maps with snappable meshes
(IEEE, 2022-04-20) Silva, Rafael Castro e; Fachada, Nuno; Andrade, Diogo de; Códices, Nélio; Faculdade de Engenharia
In this paper we present a technique for procedurally generating 3D maps using a set of premade meshes which snap together based on designer-specified visual constraints. The proposed approach avoids size and layout limitations, offering the designer control over the look and feel of the generated maps, as well as immediate feedback on a given map’s navigability. A prototype implementation of the method, developed in the Unity game engine, is discussed, and a number of case studies are analyzed. These include a multiplayer game where the method was used, together with a number of illustrative examples which highlight various parameterizations and piece selection methods. The technique can be used as a designer-centric map composition method and/or as a prototyping system in 3D level design, opening the door for quality map and level creation in a fraction of the time of a fully human-based approach. INDEX TERMS : 3D maps, computer games, designer-centric methods, layout, procedural content generation (PCG).
Comparing Freshman and doctoral engineering students in design: mapping with a descriptive framework
(Edições Universitárias Lusófonas, 2019-07-29) Marques, Pedro Carmona; 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.
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
O contributo da igualdade de género para as operações na Guarda Nacional Republicana
(Revista Ibérica de Sistemas e Tecnologias de Informação, 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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