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2020
Dinis, D., A. P. Teixeira, and Guedes C. Soares. "Probabilistic approach for characterising the static risk of ships using Bayesian networks." Reliability Engineering & System Safety. 203 (2020): 107073. AbstractWebsite
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Pinho, Fernando F. S., Pedro C. C. Lamas, and Gonçalo C. O. Teotónio. "Consolidation of soft sandstones used in ancient constructions. Application to a case study." International Journal of Architectural Heritage.DOI: 10.1080/15583058.2020.1777596 (2020).
Morais, C., J. Terroso, and H. Rocha. "E de repente tudo mudou… - Editorial." Educação e Matemática. 155 (2020): 1.Website
Tekinerdogan, Bedir, Dominique Blouin, Hans Vangheluwe, Miguel Goulão, Paulo Carreira, and Vasco Amaral Multi-Paradigm Modelling Approaches for Cyber-Physical Systems. Elsevier, 2020.
Torabian, Ala, Brisid Isufi, Davood Mostofinejad, and António Pinho Ramos. "Shear and flexural strengthening of deficient flat slabs with post-installed bolts and CFRP composites bonded through EBR and EBROG." Structural Concrete. n/a (2020). AbstractWebsite

Abstract Fiber reinforced polymer (FRP) composites can be efficient for flexural strengthening of flat slabs if debonding of the FRP is postponed. However, with the increase of the flexural capacity, the flat slab becomes more susceptible to punching shear failure. In this context, four flexural or simultaneous flexural and punching shear retrofitting systems are investigated in this study to strengthen a flexure-deficient flat slab. Externally Bonded Reinforcement on Grooves (EBROG) and externally bonded reinforcement (EBR) methods are used for flexural strengthening in two cases: slabs without punching shear reinforcement and with post-installed shear bolts as shear reinforcement. According to the results, flexural strengthening of the slab using the EBR and EBROG techniques increased its load capacity by 12% and 21%, respectively. Simultaneous flexural and shear strengthening of the slab using the EBROG technique was the most effective, leading to a 57% enhancement of the load capacity. For specimens whose failure was governed by punching, comparing the results with code predictions showed that Eurocode and ACI (and the respective guide documents fib bulletin 90 and ACI 440.2R) overestimated the capacity of these specimens. In cases where failure was governed by flexure, a simple application of the yield line theory predicted reasonably well the load capacity of the specimens.

Torres, D., C. Pimentel, and S. Duarte. "Shop floor management system in the context of smart manufacturing: a case study." International Journal of Lean Six Sigma,. 11.5 (2020): 837-862.
Torres, Marta, João Correia de Freitas, and Mônica Mesquita. "Coconstrução de um museu virtual. {Literacia}, sustentabilidade e emancipação na disseminação do património cultural das comunidades de pescadores.". Lisboa 2020. Abstract

No contexto do Observatório de Literacia Oceânica, o estudo da coconstrução de um museu virtual online investiga a aprendizagem dos alunos pertencentes às comunidades piscatórias, contribuindo para a literacia histórica. O envolvimento em tarefas concretas associadas à aprendizagem é considerado, consensualmente, um fator de motivação. No presente estudo trabalharam as artes da pesca artesanal, enquadradas por conteú dos da disciplina de História. Utilizando ambientes tecnologicamente enriquecidos, pretende-se compreender as interações entre o conhecimento formal e informal destes alunos, desenvolvendo-se o estudo de forma a que os conhecimentos sejam signi{\textbackslash}icativos e usáveis, promovendo a intervenção na sociedade, enquanto agentes de mudança. A metodologia assentou num estudo empı́rico qualitativo, com base na etnogra{\textbackslash}ia crı́tica, combinado com design-based research, para a construção do protótipo do museu virtual online. As estratégias de ação, técnicas de recolha e aná lise de dados desenvolveram-se num contexto de observação participativa, notas de campo e aplicação de vários instrumentos, bem como na coconstrução do protótipo por aproximações sucessivas estruturantes da plataforma digital selecionada. Constatou-se a ausência de interação entre os saberes formais e informais dos alunos, um desconhecimento da história das suas comunidades, mas também a valorização das histórias de famı́lia. Os alunos foram observadores crı́ticos das suas práticas reconhecendo, por exemplo, a desvalorização dos seus saberes informais e a sua falta de relação com os conteú dos da disciplina de História. Neste processo identi{\textbackslash}icou-se a necessidade de introduzir temáticas relacionadas com a Literacia Histórica, História das Comunidades Capariquenses e Sustentabilidade, considerando-o o meio privilegiado para a disseminação do seu património cultural.

Torabian, Ala, Brisid Isufi, Davood Mostofinejad, and António Pinho Ramos. "Flexural strengthening of flat slabs with FRP composites using EBR and EBROG methods." Engineering Structures. 211 (2020): 110483. AbstractWebsite

One of the major disadvantages of conventional fibre-reinforced polymer (FRP) strengthening techniques is the premature debonding of the FRP, leading to an underutilization of the materials. The externally bonded reinforcement on grooves (EBROG) method, which has been proven successful in postponing debonding in several structural applications, is examined in this study for the first time for realistic conditions in flat slabs. To this end, two different layouts of the strengthening solution are tested under concentric monotonic loading: one representing roof-level slab-column connections in which carbon FRP (CFRP) sheets are laid on top of the joint region (cross layout); and another one representing intermediate floors, in which the aforementioned layout is not possible due to the presence of the column (grid layout). For each layout, two FRP bonding techniques are used: conventional externally bonded reinforcement (EBR) and EBROG. Another specimen, without FRP strengthening, is used as a reference. It is shown that the EBROG technique is effective in postponing debonding for both layouts. Compared to the specimens in which EBR was used, the load capacity was increased in case of EBROG by 36% when FRP sheets were bonded on top of the joint (cross layout) and by 15% when sheets were attached outside the joint region (grid layout). Debonding strains are shown to be significantly higher in the case of EBROG compared to EBR. The experimentally observed debonding strains were compared with code provisions and predictions of models from the literature. A simple calculation method giving reasonably good results for the load capacity of the FRP-strengthened specimens is presented.

Torres, Marta, João Correia de Freitas, and Mônica Mesquita. "Historical {Literacy}: a {Virtual} {Museum} for the {Dissemination} of the {Cultural} {Heritage} of {Fishing} {Communities}." Proceedings of {ICERI} 2020 {Conference}. Sevilha: INTED, 2020. 6404-6410. Abstract

This project is inserted in Observatório de Literacia Oceânica, and its aim is the co-construction of a virtual museum of the Fishery Arts, based on History concepts and contents related with formal and informal knowledge. In these communities, the oral and intergenerational transmission of life stories occurs mainly within the family circle. Our main purpose was to find ways that allowed students to acquire usable and significant pasts, and not only fixed histories. The acquisition of historical literacy can change the way they apprehend and make use of knowledge, turning them in to agents of change, disseminators of their cultural heritage, with the help of a technologically enriched environment that enables network communication. The access to digital education should promote students' autonomy and responsibility when constructing knowledge. In the present study, artisanal fishing was the object of study, related to the contents of the discipline of History. Making use of technologically enriched environments we intended to analyse how the interactions between the formal and informal knowledge of these students occurred, developing the study in such a way that their knowledge could be meaningful and usable. It is intended to promote their intervention in society as agents of change, identifying and resolving problems associated with the communities to which they belong. In a perspective of curricular innovation, and considering that a sustainable development implies a change of paradigm in education, the adoption of differentiated, transformative pedagogies aiming an active learning, involving direct participation, collaboration and problem solving for the promotion of school success, it is intended to create a space for critical reflection, generating new knowledge and knowledge shared and enriched so that students participate in the construction of knowledge in order to make it meaningful and usable. Participation and negotiation amongst participants, within a perspective of shared responsibility and active citizenship, promotes cohesion and equality. We have considered the context of the school community and the context of the community in which the project is inserted, so that the tasks / knowledges that students have, can become meaningful and promote the quality and sustainability of the environment in which they are inserted. Education faces challenges that are a reflection of society’s problems. In the search for solutions it is essential the participation and collaboration of students who, with their formal and informal knowledge, can address problems that have cultural, social, political, economic and environmental impacts in their communities, as well as a local, regional and global scope, both in present and past times. Using digital environments and instruments we will try to understand how the interactions between formal and informal knowledge take place and how the performance of students from the fishing communities can be improved. Keywords: historical literacy; formal and informal knowledge; virtual museum.

Lapi, Massimo, Lorenzo Secci, Emanuele Teoni, Antonio Pinho Ramos, and Maurizio Orlando. "A hybrid method for the calibration of finite element models of punching-shear in R/C flat slabs." Computers & Structures. 238 (2020): 106323. AbstractWebsite

The paper is focused on the calibration of non-linear 3D finite element (FE) analyses to simulate punching failure of R/C flat slabs. The calibration procedure is developed with reference to the code ABAQUS, which is one of the most used computer codes in nonlinear modelling of R/C structures. Generally, the calibration of a nonlinear FE model is grounded on one test only, so its reliability could be limited. Here a hybrid method for the calibration of FE models of R/C flat slabs failing in punching is proposed and discussed. The method consists in calibrating input data by comparison of finite element model (FEM) results with both experimental data and predictions provided by analytical models. The procedure allows for a consistent calibration to be performed, valid for a wide range of longitudinal reinforcement ratios, from 0.5% to 2.00%, and concrete grades, from C20/25 to C50/60. A case study is investigated using the proposed method. Results show that calibrated values of the fracture energy lie between those provided by Model Code 1990 and Model Code 2010. From the new calibration procedure, a relationship between fracture energy and concrete compressive strength is also derived and blind analyses are performed to check its reliability against experimental results.

Santos, J. P., J. Machado, Guojie Bian, Nancy Paul, M. Trassinelli, P. Amaro, M. Guerra, C. I. Szabo, A. Gumberidze, J. M. Isac, J. P. Santos, J. P. Desclaux, and P. Indelicato. "Reference-free measurements of the 1s2s2p2P1/2,3/2o\rightarrow1s22s2S1/2 and 1s2s2p4P5/2\rightarrow1s22s2S1/2 transition energies and widths in lithiumlike sulfur and argon ions." Physical Review A (2020). AbstractWebsite
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Bahubalindruni, Pydi Ganga, Pedro Barquinha, Bhawna Tiwari, Maria Pereira, Ana Santa, Jorge Martins, Ana Rovisco, Vitor Tavares, Rodrigo Martins, and Elvira Fortunato. "{Rail-to-Rail Timing Signals Generation Using InGaZnO TFTs for Flexible X-Ray Detector}." IEEE Journal of the Electron Devices Society. 8 (2020): 157-162. AbstractWebsite

This paper reports on-chip rail-to-rail timing signals generation thin-film circuits for the first time. These circuits, based on a-IGZO thin-film transistors (TFTs) with a simple staggered bottom gate structure, allow row and column selection of a sensor matrix embedded in a flexible radiation sensing system. They include on-chip clock generator (ring oscillator), column selector (shift register) and row-selector (a frequency divider and a shift register). They are realised with rail-to-rail logic gates with level-shifting ability that can perform inversion and NAND logic operations. These logic gates are capable of providing full output swing between supply rails, $V_{DD}$ and $V_{SS}$ , by introducing a single additional switch for each input in bootstrapping logic gates. These circuits were characterised under normal ambient atmosphere and show an improved performance compared to the conventional logic gates with diode connected load and pseudo CMOS counterparts. By using these high-performance logic gates, a complete rail-to-rail frequency divider is presented from measurements using D-Flip Flop. In order to realize a complete compact system, an on-chip ring oscillator (output clock frequency around 1 kHz) and a shift register are also presented from simulations, where these circuits show a power consumption of 1.5 mW and 0.82 mW at a supply voltage of 8 V, respectively. While the circuit concepts described here were designed for an X-ray sensing system, they can be readily expanded to other domains where flexible on-chip timing signal generation is required, such as, smart packaging, biomedical wearable devices and RFIDs.

Machado, J., Guojie Bian, Nancy Paul, M. Trassinelli, P. Amaro, M. Guerra, C. I. Szabo, A. Gumberidze, J. M. Isac, J. P. Santos, J. P. Desclaux, and P. Indelicato. "{Reference-free measurements of the 1s2s2p2P1/2,3/2o$\rightarrow$1s22s2S1/2and 1s2s2p4P5/2$\rightarrow$1s22s2S1/2transition energies and widths in lithiumlike sulfur and argon ions}." Physical Review A. 101 (2020): 062505. AbstractWebsite
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2019
Torres-González, Arturo, Alfonso Alcántara, Vasco Sampaio, Jesús Capitán, Bruno Guerreiro, Rita Cunha, and Anibal Ollero. "Distributed Mission Execution for Aerial Cinematography with Multiple Drones." Workshop on Signal Processing Computer vision and Deep Learning for Autonomous Systems, EUSIPCO2019. 2019. Abstract
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Cunha, Rita, Miguel Malaca, Vasco Sampaio, Bruno Guerreiro, Paraskevi Nousi, Ioannis Mademlis, Anastasios Tefas, and Ioannis Pitas. "Gimbal Control for Vision-based Target Tracking." Workshop on Signal Processing Computer vision and Deep Learning for Autonomous Systems, EUSIPCO2019. 2019. Abstract
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Mademlis, Ioannis, Arturo Torres-González, Jesús Capitán, Rita Cunha, Bruno Guerreiro, Alberto Messina, Fulvio Negro, Cedric Le Barz, Tiago Gonçalves, and Anastasios Tefas. "A Multiple-UAV Software Architecture for Autonomous Media Production." Workshop on Signal Processing Computer vision and Deep Learning for Autonomous Systems, EUSIPCO2019. 2019. Abstract
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Torrisi, Giacomo, João S. Luis, Olalla Sanchez-Sobrado, Rosario Raciti, Manuel J. Mendes, Hugo Águas, Elvira Fortunato, Rodrigo Martins, and Antonio Terrasi. "{Colloidal-structured metallic micro-grids: High performance transparent electrodes in the red and infrared range}." Solar Energy Materials and Solar Cells. 197 (2019): 7-12. Abstract

One of the most promising approaches to produce industrial-compatible Transparent Conducting Materials (TCMs) with excellent characteristics is the fabrication of TCO/metal/TCO multilayers. In this article, we report on the electro-optical properties of a novel high-performing TCO/metal/TCO structure in which the intra-layer is a micro-structured metallic grid instead of a continuous thin film. The grid is obtained by evaporation of Ag through a mask of polystyrene colloidal micro-spheres deposited by the Langmuir-Blodgett method and partially dry-etched in plasma. IZO/Ag grid/IZO structures with different thicknesses and mesh dimensions have been fabricated, exhibiting excellent electrical characteristics (sheet resistance below 10 $Ømega$/□) and particularly high optical transmittance in the near-infrared spectral region as compared to planar (unstructured) TCM multilayers. Numerical simulations were also used to highlight the role of the Ag mesh parameters on the electrical properties.

Dinis, Duarte, Ana Barbosa-Póvoa, and Ângelo Palos Teixeira. "Valuing data in aircraft maintenance through big data analytics: A probabilistic approach for capacity planning using Bayesian networks." Computers & Industrial Engineering. 128 (2019): 920-936. AbstractWebsite
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Torabian, Ala, Brisid Isufi, Davood Mostofinejad, and António Pinho Ramos. "Behavior of thin lightly reinforced flat slabs under concentric loading." Engineering Structures. 196 (2019): 109327. AbstractWebsite

The current research aims to study the behavior of thin reinforced concrete (RC) slabs under concentrated loads as well as to investigate the application of Critical Shear Crack Theory (CSCT) to such slabs. For this purpose, four square 100-mm-thick slabs were cast and subjected to concentrated punching monotonic loading. The experimental parameters were the flexural reinforcement ratio, 0.38% and 1.00%, and the presence or absence of shear headed stud reinforcement. It is shown that the failure criteria of CSCT describe reasonably well the observed failure modes and the ultimate loads of the specimens. However, attention is brought to some peculiarities in the analytical derivation of the load-rotation curve for thin lightly reinforced flat slabs, in which large deformations are experienced. Results showed that in such slabs, the behavior can be highly influenced by the post-yield stress-strain curve of the flexural steel reinforcement. As a result, the constitutive law of steel reinforcement should be explicitly taken into account in such cases. The versatility of CSCT to adapt to these conditions is demonstrated.

Teubig, P., P. Remmels, P. Klenze, H. Alvarez-Pol, E. Alves, J. M. Boillos, P. Cabanelas, R. C. da Silva, D. Cortina-Gil, J. Cruz, D. Ferreira, M. Fonseca, D. Galaviz, E. Galiana, R. Gernhäuser, D. González, A. Henriques, A. P. Jesus, H. Luís, J. Machado, L. Peralta, J. Rocha, A. M. Sánchez-Benítez, H. Silva, and P. Velho. "Challenging the Calorimeter CALIFA for FAIR Using High Energetic Photons." Eds. José-Enrique García-Ramos, María V. Andrés, José Lay A. Valera, Antonio M. Moro, and Francisco Pérez-Bernal. Cham: Basic Concepts in Nuclear Physics: Theory, Experiments and Applications, 2019. 245-246. Abstract
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Secci, L., E. Teoni, M. Lapi, M. Orlando, and a Ramos. "Finite element analysis of punching shear of R/C slabs: A hybrid approach for model calibration." Proceedings of the fib Symposium 2019: Concrete - Innovations in Materials, Design and Structures. 2019. 643-650. Abstract
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Torres, Marta, João C. Freitas, and Mónica Mesquita. "Literacy in {Schools}: a {Virtual} {Museum} for the {Dissemination} of the {Cultural} {Heritage} of {Fishing} {Communities}." {ICERI2020} {Proceedings}. Granada: Fundación General UGR-Empresa y Universidad de Granada, 2019. Abstract
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Torres, Diamantino, Carina Pimentel, and Susana Duarte. "Shop floor management system in the context of smart manufacturing: a case study." International Journal Of Lean Six Sigma (2019). Abstract

Purpose: The purpose of this study intends to make a characterization of a shop floor management (SFM) system in the context of smart manufacturing, through smart technologies and digital shop floor (DSF) features. Design/methodology/approach: To attain the paper objective, a mixed method methodology was used. In the first stage, a theoretical background was carried out, to provide a comprehensive understanding on SFM system in a smart manufacturing perspective. Next, a case study within a survey was developed. The case study was introduced to characterize a SFM system, while the survey was made to understand the level of influence of smart manufacturing technologies and of DSF features on SFM. In total, 17 experts responded to the survey. Findings: Data analytics is the smart manufacturing technology that influences more the SFM system and its components and the cyber security technology does not influence it at all. The problem solving (PS) is the SFM component more influenced by the smart manufacturing technologies. Also, the use of real-time digital visualization tools is considered the most influential DSF feature for the SFM components and the data security protocols is the least influential one. The four SFM components more influenced by the DSF features are key performance indicator tracking, PS, work standardization and continuous improvement. Research limitations/implications: The study was applied in one multinational company from the automotive sector. Originality/value: To the best of the authors’ knowledge, this work is one of the first to try to characterize the SFM system on smart manufacturing considering smart technologies and DSF features.