FE - Artigos de Revistas Internacionais com Arbitragem Científica

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    ParShift: a Python package to study order and differentiation in group conversations
    (Elsevier, 2023-12-01) Saraiva, Bruno David Ferreira; Carvalho, João P. Matos; Fachada, Nuno; Pita, Manuel Arturo Marques
    Collective organization in multi-party conversations emerges through the exchange of utterances between participants. While most research has focused on content-centred mechanisms that lead to emergent conversational coordination, less attention has been given to explaining conversational order based on who is addressed and who responds, especially when dealing with large conversational datasets. In this paper, we introduce a Python library, ParShift, that implements a state-of-the-art theoretical quantitative framework known as Participation Shifts. This framework enables researchers to study participant-centred order and differentiation in multi-party conversations. With ParShift, researchers can characterize conversations by quantifying the probabilities of events related to how people address each other during conversations. This library is particularly useful for studying conversation threads in social networks, parliamentary debates, team meetings, or student debates on a large scale. Keywords: Small groups Social interaction Participation shifts Interpersonal coordination Turn-taking Emergent social behaviour
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    Revisão sistemática da literatura sobre viés de género e aprendizagem máquina na segurança
    (Iberian Journal of Information System and Technologies, 2023-10) Malheiro, Luís Carlos Rodrigues; Bessa, Fernando José da Conceição; Reis, João Carlos Gonçalves Dos; Saraiva, Luís Eduardo
    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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    O contributo da igualdade de género para as operações na Guarda Nacional Republicana
    (Iberian Journal of Information Systems and Technologies, 2023-10) Malheiro, Luís Carlos Rodrigues; Bessa, Fernando José da Conceição; Reis, João Carlos Gonçalves Dos; Saraiva, Luís Eduardo
    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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    Generating multidimensional clusters with support lines
    (Elsevier, 2023) Fachada, Nuno; de Andrade, Diogo
    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
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    Analyzing the attractiveness of Businesses to receive Investments for a creative and innovative transition to a circular economy: the case of the textile and fashion industry
    (MDPI, 2023-04-13) Silva, Wesley Douglas Oliveira; Fontana, Marcele Elisa; Almeida, Bianca; Marques, Pedro Carmona; Vidal, Raphaela
    Excessive and often compulsive consumption has given the textile–fashion industry the reputation of being one of the industries causing the most pollution in today’s world. For this reason, there is a necessity for a transition from a linear to a circular approach in the textile–fashion industry. However, this is not an easy task, especially when considering the investments that must be made to put a circular economy structure into practice. In this sense, the transition to a circular economy in the textile–fashion industry presents a unique opportunity for businesses to attract investments to support this transition by leveraging creativity and innovation to reduce waste, minimize resource consumption, and increase the longevity of products and materials. Therefore, this study sets out to develop a multicriteria decision support model to measure the attractiveness of businesses to receive investments that aim at aiding the transition to the circular economy. The model uses the “play card” from Simos’ procedure and the Normalize software that provide a comprehensive, consistent, and transparent approach to decision making, which can help investors to evaluate the attractiveness of investment opportunities and identify businesses that have the potential for long-term success in the circular economy. Hence, catalyzing and obstructing factors of the circular economy discussed in the literature were selected to underpin the analysis model and to draw up robust investment recommendations to the investors. In addition to the scientific contributions of the model, indications are also provided to the private sector, public policy makers, and society on how sustainability can be driven by the circular economy.
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    MN-DS: A Multilabeled News Dataset for News Articles Hierarchical Classification
    (MDPI, 2023-04-23) Petukhova, Alina; Fachada, Nuno
    This article presents a dataset of 10,917 news articles with hierarchical news categories collected between 1 January 2019 and 31 December 2019. We manually labeled the articles based on a hierarchical taxonomy with 17 first-level and 109 second-level categories. This dataset can be used to train machine learning models for automatically classifying news articles by topic. This dataset can be helpful for researchers working on news structuring, classification, and predicting future events based on released news. Keywords: news dataset; text classification; NLP; media topic taxonomy
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    A Rapid Review on the Use of Free and Open Source Technologies and Software Applied to Precision Agriculture Practices
    (MDPI, 2023-03-24) Santos, Rogério P. dos; Fachada, Nuno; Beko, Marko; Leithardt, Valderi, orient.
    Technology plays a crucial role in the management of natural resources in agricultural production. Free and open-source software and sensor technology solutions have the potential to promote more sustainable agricultural production. The goal of this rapid review is to find exclusively free and open-source software for precision agriculture, available in different electronic databases, with emphasis on their characteristics and application formats, aiming at promoting sustainable agricultural production. A thorough search of the Google Scholar, GitHub, and GitLab electronic databases was performed for this purpose. Studies reporting and/or repositories containing up-to-date software were considered for this review. The various software packages were evaluated based on their characteristics and application formats. The search identified a total of 21 free and open-source software packages designed specifically for precision agriculture. Most of the identified software was shown to be extensible and customizable, while taking into account factors such as transparency, speed, and security, although some limitations were observed in terms of repository management and source control. This rapid review suggests that free and open-source software and sensor technology solutions play an important role in the management of natural resources in sustainable agricultural production, and highlights the main technological approaches towards this goal. Finally, while this review performs a preliminary assessment of existing free and open source solutions, additional research is needed to evaluate their effectiveness and usability in different scenarios, as well as their relevance in terms of environmental and economic impact on agricultural production.
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    Digital transformation: A meta-review and guidelines for future research
    (Elsevier, 2023) Reis, João; Melão, Nuno
    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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    Uavnoma: A UAV-NOMA Network Model under Non-Ideal Conditions
    (Ubiquity Press, 2022-10-17) Lima, Brena; Fachada, Nuno; Dinis, Rui; Costa, Daniel Benevides da; Beko, Marko
    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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    Economic disposal quantity of leftovers kept in storage: a Monte Carlo simulation method
    (2019) Assis, Rui; Marques, Pedro Carmona; Santos, José Oliveira; Vidal, Raphaela
    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
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    A igualdade de género na União Europeia: a implementação da agenda mulheres, paz e segurança
    (Iberian Journal of Information Systems and Technologies, 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
    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.
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    Where are smart cities heading? A meta-review and guidelines for future research
    (MDPI, 2022) Reis, João Carlos Gonçalves dos; Marques, Pedro Alexandre; Marques, Pedro Carmona
    (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.
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    Unity Snappable Meshes
    (Elsevier, 2022-08-01) Fachada, Nuno; Silva, Rafael Castro e; Andrade, Diogo de; Códices, Nélio
    The Snappable Meshes algorithm procedurally generates 3D maps for computer games by iteratively selecting and linking pre-built map pieces via designer-specified connectors. In this paper we present an implementation of this algorithm in the Unity game engine, describing its architecture and discussing core implementational solutions. A number of examples illustrate the potential of the algorithm and the capabilities of the software. We assess the application’s impact on past and ongoing research, and how it can be improved to support future research questions. Keywords: Procedural content generation (PCG) ; Computer games ; Layout ; Designer-centric methods ;3D maps ; Unity game engine
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    TextCL: a Python package for NLP preprocessing tasks
    (Elsevier, 2022-07-01) Petukhova, Alina; Fachada, Nuno
    Preprocessing text data sets for use in Natural Language Processing tasks is usually a time-consuming and expensive effort. Text data, normally obtained from sources such as, but not limited to, web scraping, scanned documents or PDF files, is typically unstructured and prone to artifacts and other types of noise. The goal of the TextCL package is to simplify this process by providing multiple methods suited for text data preprocessing. It includes functionality for splitting texts into sentences, filtering sentences by language, perplexity filtering, and removing duplicate sentences. Another functionality offered by the TextCL package is the outlier detection module, which allows to identify and filter out texts that are different from the main topic distribution of the data set. This method allows selecting one of several unsupervised outlier detection algorithms, such as TONMF (block coordinate descent framework), RPCA (robust principal component analysis), or SVD (singular value decomposition) and apply it to the text data. Keywords: Natural language processing ; Text filtering ; Outlier detection
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    Retail system scenario modeling using fuzzy cognitive maps
    (MDPI, 2022) Petukhova, Alina; Fachada, Nuno
    A retail business is a network of similar-format grocery stores with a sole proprietor and a well-established logistical infrastructure. The retail business is a stable market, with low growth, limited customer revenues, and intense competition. On the system level, the retail industry is a dynamic system that is challenging to represent due to uncertainty, nonlinearity, and imprecision. Due to the heterogeneous character of retail systems, direct scenario modeling is arduous. In this article, we propose a framework for retail system scenario planning that allows managers to analyze the effect of different quantitative and qualitative factors using fuzzy cognitive maps. Previously published fuzzy retail models were extended by adding external factors and combining expert knowledge with domain research results. We determined the most suitable composition of fuzzy operators for the retail system, highlighted the system’s most influential concepts, and how the system responds to changes in external factors. The proposed framework aims to support senior management in conducting flexible long-term planning of a company’s strategic development, and reach its desired business goals. Keywords: retail; complex systems; fuzzy cognitive maps; scenario planning
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    Procedural generation of 3D maps with snappable meshes
    (IEEE, 2022-04-20) Silva, Rafael Castro e; Fachada, Nuno; Andrade, Diogo de; Códices, Nélio
    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).
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    Drop Project: an automatic assessment tool for programming assignments
    (Elsevier, 2022-06-01) Cipriano, Bruno Pereira; Fachada, Nuno; Alves, Pedro
    Automated assessment tools (AATs) are software systems used in teaching environments to automate the evaluation of computer programs implemented by students. These tools can be used to stimulate the interest of computer science students in programming courses by providing quick feedback on their work and highlighting their mistakes. Despite the abundance of such tools, most of them are developed for a specific course and are not production-ready. Others lack advanced features that are required for certain pedagogical goals (e.g. Git integration) and/or are not flexible enough to be used with students having different computer literacy levels, such as first year and second year students. In this paper we present Drop Project (DP), an automated assessment tool built on top of the Maven build automation software. We have been using DP in our teaching activity since 2018, having received more than fifty thousand submissions between projects, classroom exercises, tests and homework assignments. The tool’s automated feedback has allowed us to raise the difficulty level of the course’s projects, while the grading process has become more efficient and consistent between different teachers. DP is an extensively tested, production-ready tool. The software’s code and documentation are available in GitHub under an open-source software license. Keywords: Automated assessment ;Computer science education; Programming education ; Unit testing
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    Enlarged PLIN5-uncoated lipid droplets in inner regions of skeletal muscle type II fibers associate with type 2 diabetes
    (Elsevier, 2022-02) Fachada, Vasco; Rahkila, Paavo; Fachada, Nuno; Turpeinen, Tuomas; Kujala, Urho M.; Kainulainen, Heikki
    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
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    Defence industries and open innovation: ways to increase military capabilities of the Portuguese ground forces
    (Routledge Tailor & Francis, 2022) Reis, ‪João Carlos Gonçalves dos; Melão, Nuno; Costa, Joana; Pernica, Bohuslav
    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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    Production, characterization, and immobilization of protease from the yeast Rhodotorula oryzicola
    (Wiley, 2020) Oliveira, Juliana Mota de; Fernandes, Pedro Carlos de Barros; Benevides, Raquel Guimarães; Assis, Sandra Aparecida de
    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.