FE - Artigos de Revistas Internacionais com Arbitragem Científica

URI permanente para esta coleção:https://hdl.handle.net/10437/10765

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    A descriptive framework of the design process from a dual cognitive-engineering perspective
    (Taylor and Francis Ltd., 2014) Marques, Pedro D.B.Carmona; Silva, Arlindo José P.F.; Henriques, Elsa M.P.; Magee, Christopher L.; FE - Faculty of Engineering
    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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    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; FE - Faculty of Engineering
    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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    Economic disposal quantity of leftovers kept in storage : a Monte Carlo simulation method
    (Walter de Gruyter GmbH, 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.
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    Computational programming as a tool in the teaching of electromagnetism in engineering courses : Improving the notion of field
    (Multidisciplinary Digital Publishing Institute (MDPI), 2019) Nogueira, João; Alves, Ricardo Gaio; Marques, Pedro Carmona; FE - Faculty of Engineering; CeiED - Interdisciplinary Research Centre for Education and Development
    In this study we have attempted, firstly, to describe programming protocols developed for the teaching of an Electromagnetism course in the university degrees of Electrical Engineering and Energy Engineering, and secondly, to evaluate students’ satisfaction with the simulation practices through MATLAB®programming. The main objective of the protocols is to allow students to model and visualize the electric field and magnetic field (both static) and understand the approximation that is made when considering certain distributions of electric charges and electric currents. To evaluate the usefulness of this computational methodology, eighteen students from the two engineering degrees answered a questionnaire with seven questions related to the Electromagnetism course and to the benefits of using computer programming. Their answers are measured by a Likert scale. From the analysis of the results, we can conclude, in a general way, that the use of this methodology has positive effects in the learning of Electromagnetism in these two degrees.
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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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    Microfluidic bioreactors for enzymatic synthesis in packed-bed reactors—Multi-step reactions and upscaling
    (Elsevier B.V., 2020-11-10) Brás, Eduardo J.S.; Domingues, Cristiana; Chu, Virginia; Fernandes, Pedro; Conde, João Pedro; HEI-LAB - Human Environment Interaction Lab
    Enzymatic synthesis of biochemical commodities is of upmost importance as it represents a greener alternative to traditional chemical synthesis and provides easier downstream processing strategies compared to fermentation-based processes. A microfluidic system used to optimize the enzymatic production of both levodopa (L-DOPA) and dopamine in both single-step and multistep-reaction sequences with yield of approximately 30 % for L-DOPA production and 70 % for dopamine production is presented. The system for L-DOPA production was then up-scaled (780-fold increase) to a milliliter scale system by maintaining similar mass transport properties resulting in the same yield, space-time yield and biocatalyst yield as its microscale counterpart. The results obtained for yield and biocatalyst yield (351.7 mgL-DOPA mg−1Tyr h−1) were similar to what is reported in the literature for similar systems, however the space-time yield (0.806 mgL-DOPA L−1 h−1) was smaller. This work demonstrates a microfluidic bioreactor that can be used for complex optimizations that can be performed rapidly while reducing the consumption of reagents by immobilizing the catalyst on a carrier which can then be used in a packed-bed reactor, thus extending the enzyme life span.
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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 - Cognitive and People-centric Computing
    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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    Digital transformation : a meta-review and guidelines for future research
    (Elsevier Ltd., 2023-01) Reis, João; Melão, Nuno; RCM2+ - Research Centre in Asset Management and System Engineering
    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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    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
    (Multidisciplinary Digital Publishing Institute (MDPI), 2023-04-13) Silva, Wesley Douglas Oliveira; Fontana, Marcele Elisa; Almeida, Bianca; Marques, Pedro Carmona; Vidal, Raphaela; FE - Faculty of Engineering
    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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    A rapid review on the use of free and open source technologies and software applied to precision agriculture practices
    (Multidisciplinary Digital Publishing Institute (MDPI), 2023-03-24) Santos, Rogério P. dos; Fachada, Nuno; Beko, Marko; Leithardt, Valderi; FE - Faculty of Engineering; COPELABS - Cognitive and People-centric Computing
    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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    MN-DS: A Multilabeled News Dataset for News Articles Hierarchical Classification
    (Multidisciplinary Digital Publishing Institute (MDPI), 2023-04-23) Petukhova, Alina; Fachada, Nuno; FE - Faculty of Engineering; COPELABS - Cognitive and People-centric Computing
    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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    Drop Project : an automatic assessment tool for programming assignments
    (Elsevier B.V., 2022-06-01) Cipriano, Bruno Pereira; Fachada, Nuno; Alves, Pedro; COPELABS - Cognitive and People-centric Computing
    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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    Procedural generation of 3D maps with snappable meshes
    (Institute of Electrical and Electronics Engineers Inc., 2022-04-20) Silva, Rafael Castro e; Fachada, Nuno; Andrade, Diogo de; Códices, Nélio; COPELABS - Cognitive and People-centric Computing
    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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    Politics, power, and influence : defense industries in the post-cold war
    (Multidisciplinary Digital Publishing Institute (MDPI), 2021-01) Dos Reis, João Carlos Gonçalves; RCM2+ - Research Centre in Asset Management and System Engineering
    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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    Generating multidimensional clusters with support lines
    (Elsevier B.V., 2023) Fachada, Nuno; de Andrade, Diogo; COPELABS - Cognitive and People-centric Computing
    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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    A survey on sustainable product development
    (Elsevier B.V., 2019) Marques, Pedro Carmona; Charmier, Maria Adília Januário; Santos, José Oliveira; FE - Faculty of Engineering
    The emergent field of sustainable product development has been rapidly evolving in several academic publications. Furthermore, sustainable product development is the basis for innovative products (and services). The analysis begins by identifying published studies within the last five years. A systematic mapping of the field evolution overtime is performed by identifying areas of current research interests and potential directions for future research. The findings will provide a roadmap for further investigations in this field.
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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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    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+ - Research Centre in Asset Management and System Engineering
    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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    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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    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; FE - Faculty of Engineering
    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.