Percorrer por tipo de recurso "Artigo científico"
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- A 2020 perspective on “Online guest profiling and hotel recommendation”Publication . Veloso, Bruno M.; Leal, Fátima; Malheiro, Benedita; Burguillo, Juan CarlosTourism crowdsourcing platforms accumulate and use large volumes of feedback data on tourism-related services to provide personalized recommendations with high impact on future tourist behavior. Typically, these recommendation engines build individual tourist profiles and suggest hotels, restaurants, attractions or routes based on the shared ratings, reviews, photos, videos or likes. Due to the dynamic nature of this scenario, where the crowd produces a continuous stream of events, we have been exploring stream-based recommendation methods, using stochastic gradient descent (SGD), to incrementally update the prediction models and post-filters to reduce the search space and improve the recommendation accuracy. In this context, we offer an update and comment on our previous article (Veloso et al., 2019a) by providing a recent literature review and identifying the challenges laying ahead concerning the online recommendation of tourism resources supported by crowdsourced data.
- A systematic literature review on maturity models for information systems in higher education institutionsPublication . João Vidal de Carvalho; Vidal de Carvalho, Joao; Pereira, Rui Humberto; Álvaro RochaMaturity models have been introduced over the last five decades as guides and references for information system (IS) management in organizations from different sectors. In the education sector, maturity models have also been used to evaluate higher education institutions (HEIs) across several dimensions, such as information and communication technology (ICT), management, process management, course curricula, course/HEI accreditation, e-/m-learning, online courses and pedagogical strategies. In fact, HEIs are faced with enormous complexity due to the specificity and quantity of their processes. Based on the guidelines concerning a methodology for a systematic literature review, the maturity models of different subareas of education are identified and categorized in this paper. For each maturity model associated with HEIs’ ISs, the appropriate methodology for development and validation is identified, as well as the scope, stages and their dimensional characteristics. This study highlights the need to develop an IS maturity model that supports HEIs in their core business activities and management.
- Architecture of a maturity model for information systems in higher education institutions: multiple case study for dimensions identificationPublication . Rui Humberto Pereira; Pereira, Rui Humberto; joão vidal de carvalho; Vidal de Carvalho, Joao; Álvaro RochaHigher education institutions (HEIs) are complex and dynamic organizations in terms of information management, forcing their information systems to respond to enormous challenges and threats. In order to evaluate the HEIs’ information systems, we propose the development of a maturity model capable of supporting the role of HEI’s managers, as well as accreditation agencies, in the assessment of the maturity of these systems, thus, promoting continuous improvement. In this paper, we present and discuss our proposal for an architecture of the maturity model being developed. This one is based on a two-dimensional architecture composed of vertical and horizontal dimensions. We selected a multi-case study approach, based on five Portuguese HEIs, and reviewed the literature to identify the dimensions. This case study was supported by interviews with experts from the selected HEI. The results of this research work were both encouraging and promising amongst the interviewed experts, revealing a high level of acceptance of the general model architecture, as well as positive expectations about its usefulness in the future. The development of our maturity model is carried out by following a formal methodology specially designed to support the construction of this type of model.
- Confined RuP2 Nanoparticles in N,P,S-tridoped Carbon as Superior Electrocatalyst for pH-Wide Hydrogen EvolutionPublication . Yu Sun, Haibo Li, Suyuan Zeng, Rui Li, Qingxia Yao, Hongyan Chen, Yinghua Wang, Konggang Qu, Lijian MengHydrogen has been deemed as the ideal energy source and carrier due to its unmatched energy efficiency and sustainability. Nevertheless, there is a pressing need to develop cost-effective materials to replace costly Pt in the hydrogen evolution reaction (HER), and the electrocatalysts with low overpotential and robust stability under various conditions is a particularly significant concern. In this study, a straightforward and effective approach was proposed for the precise synthesis of RuP2 nanoparticles encapsulated in N, P, S-tridoped carbon, which involves utilizing zinc pyrithione, phytic acid and Ru salt as starting materials. The effect of different Ru loadings on the morphology and structures of the composite catalysts was examined carefully. The obtained composites exhibit superior alkaline activity surpassing commercial Pt/C and comparable acidic and neutral activity as well as excellent pH-wide stability. DFT computations reveal the integration of RuP2 with tridoped carbon can tailor the electronic structure of Ru active sites by interfacial electron transfer, thus optimizing the adsorption energy and promoting the HER activity. The benign graphitization of doped carbon and porous structures ensure the smooth charge and mass transfer during HER process. The cost-effective and straightforward synthesis methods presented in this work offer a promising alternative to commercial Pt/C for practical hydrogen-related applications.
- "Educação a quanto obrigas": Quando se torna o currículo um 'extra' ou um 'enriquecimento'?Publication . Duarte, Pedro; Duarte, Pedro; Coelho, Carina; Coelho, CarinaO debate sobre educação na esfera pública tem vindo a caracterizar-se por um esvaziamento educativo, isto é, pela desconsideração de conceitos, valores e preocupações fundamentais e historicamente constituintes da reflexão em educação. Desprovida dos seus suportes axiológicos, a discussão educativa orienta-se, sobretudo, para uma vocação utilitária, de resposta às necessidades da economia e do mercado, justificada à luz das teorias do capital humano. Esta ocupação discursiva estende-se aos tempos de educação (e de vida) das crianças, os quais, altamente institucionalizados, são decididos de forma heterónoma e em função de um eventual benefício escolar ou vantagem competitiva, no mercado global. Com este artigo procuramos contribuir para uma reflexão sobre infância, tempo livre e ludicidade que se oriente por fundamentos eminentemente educativos e que se liberte de referenciais escolares e instrumentalistas da educação. Ou, por outras palavras, para pensarmos as possibilidades de conjugar harmoniosamente o currículo, a liberdade e a ludicidade
- Gestão das organizações educativas: um posicionamento críticoPublication . Moreira, Ana Isabel; Duarte, Pedro; Moreira, Ana IsabelEste artigo evidencia, sob a forma de uma reflexão teórica, a interação possível entre a investigação-ação enquanto abordagem investigativa geral e a gestão das organizações educativas, em particular as escolas, enquanto prática profissional. Mobilizando as pesquisas e os trabalhos conceptuais de diversos autores, fundamenta-se um ponto de vista que clarifica as potencialidades da investigação-ação(-participativa) no seio de uma ação de gestão da escola que assenta em pressupostos e valores democráticos, nomeadamente a agência dos diferentes intervenientes nos contextos. Simultaneamente, mostra como a gestão educativa permite o aperfeiçoamento de estruturas e de práticas, também pedagógicas, quando os agentes são realmente integrados nas ações quotidianas, nas decisões tomadas, na análise de uma realidade (social) que é distinta de todas as outras. Assume-se, assim, uma determinada perspetiva sobre assuntos como a investigação e seus contornos, a gestão e o seu papel nas organizações educativas, o lugar dos profissionais da educação nas escolas e suas diversas circunstâncias.
- Towards an encompassing maturity model for the management of higher education institutionsPublication . Pereira, Rui Humberto; Pereira, Rui Humberto; João Vidal de Carvalho; Vidal de Carvalho, Joao; Álvaro RochaMaturity models (MM) have been adopted in organisations from different sectors of activity, as guides and references for Information Systems (IS) management. In the educational field, these models have also been used to deal with the enormous complexity and demand of IS management. This paper presents a research project that aims to develop a new MM for Higher Education Institutions (HEI) that helps them to address those problems, as a useful tool for the management of their IS (and institutions as well). Thus, the MM in this area are identified, as well as the characteristics and gaps that they present, justifying the need and the opportunity for a new and comprehensive MM. Finally, we discuss the methodology for the development of MM that will be adopted for the design of the new model (called HEIMM) and the underlying reasons for its choice. At the moment, we are developing the HEIMM.
- User Reputation on E-Commerce: Blockchain-Based ApproachesPublication . Maria José Angélico Gonçalves; Rui Humberto Pereira; Marta Alexandra Guerra Magalhães Coelho; Angélico Gonçalves, Maria José; Pereira, Rui HumbertoUser trust is a fundamental issue in e-commerce. To address this problem, recommendation systems have been widely used in different application domains including social media healthcare, e-commerce, and others. In this paper, we present a systematic review of the literature in the area of blockchain-based reputation models and we discuss the obtained results, answering the initial research questions. These findings lead us to conclude that the existing systems are based on a trusted third party (TTP) to collect and store reputation data, which does not provide transparency on users’ reputation scores. In the recent literature, on the one hand, blockchain-based reputation systems have been highlighted as possible solutions to effectively provide the necessary transparency, as well as effective identity management. On the other hand, new challenges are posed in terms of user privacy and performance, due to the specific characteristics of the blockchain. According to the literature, two major approaches have been proposed based on public and permissioned blockchains. Each approach applies adjusted models for calculating reputation scores. Despite the undoubted advantages added by a blockchain, the problem is only partially solved since there is no effective way to prevent blockchain oracles from feeding the chain with false, unfair, or biased data. In our future work, we intend to explore the two approaches discussed in the literature in order to propose a new blockchain-based model for deriving user reputation scores.