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2018
Correia, Ana, Pedro Barquinha, João Marques, and João Goes. "A High-resolution ∆-Modulator ADC with Oversampling and Noise-shaping for IoT." 14th Conference on PhD Research in Microelectronics and Electronics, PRIME 2018. Prague, Czech Republic: IEEE, 2018.
Conchinha, Cristina, Susana Exposto, Dulce Lopes, and João Correia de Freitas. "Storytelling, robótica e inclusión: {Un} estudio de caso sobre el potencial inclusivo de la robótica virtual." 2018. Abstract

Presentamos un estudio de caso con una clase de 15 alumnos, entre ellos un estudiante con baja visión y otro alumno con dificultades en la comunicación y el lenguaje y con trastornos emocionales y relacionales, inscritos en el tercer año del primer ciclo de la educación básica y la edad 8 y 9 años. Las actividades fueron desarrolladas por la profesora de la clase y la profesora de educación especial, en virtud de un taller de formación de profesores sobre el potencial inclusivo del simulador de robótica, RoboMind®. Fue pedido a los estudiantes qué construyesen una historia, incluyendo narrativa y escenarios, sobre los planetas y los costumbres de su ciudad, asunto abordado en este semestre por los alumnos. Los resultados mostraron que la robótica virtual, promovió la inclusión de los alumnos con NEE, la interacción y el apoyo mutuo, la estructura y organización de las ideas, la creatividad, la resolución de problemas, el desarrollo del pensamiento crítico y la adquisición de contenido transversal We present in this work a case study, with a group of 15 students, including a student with low vision and another student with communication and language difficulties and emotional disturbances. These students are in the third year and they are 8

Biscaia, H. C., C. Chastre, J. Cardoso, and N. Franco. "Analyses on the bond transfer between FRP composites and other structural materials." 9th International Conference on Fibre Reinforced Polymer (FRP) Composites in Civil engineering, CICE2018. Paris, France 2018. 8. Abstract
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Neves, F., A. Stark, N. Schell, MJ Mendes, H. Aguas, E. Fortunato, R. Martins, J. B. Correia, and A. Joyce. "{Investigation of single phase Cu2ZnSnxSb1-xS4 compounds processed by mechanochemical synthesis}." Physical Review Materials. 2 (2018). Abstract

The copper zinc tin sulfide (CZTS) compound is a promising candidate as an alternative absorber material for thin-film solar cells. In this study, we investigate the direct formation of Cu1.92ZnSnx(Sb1-x)S4 compounds [CZT(A)S], with x=1, 0.85, 0.70, and 0.50, via a mechanochemical synthesis (MCS) approach, starting from powders of the corresponding metals, zinc sulfide, and sulfur. The thermal stability of the CZT(A)S compounds was evaluated in detail by in situ synchrotron high-energy x-ray diffraction measurements up to 700 °C. The CZT(A)S compounds prepared via MCS revealed a sphalerite-type crystal structure with strong structural stability over the studied temperature range. The contribution of the MCS to the formation of such a structure at room temperature is analyzed in detail. Additionally, this study provides insights into the MCS of CZTS-based compounds: the possibility of a large-scale substitution of Sn by Sb and the production of single phase CZT(A)S with a Cu-poor/Zn-poor composition. A slight increase in the band gap from 1.45 to 1.49-1.51 eV was observed with the incorporation of Sb, indicating that these novel compounds can be further explored for thin-film solar cells.

Biscaia, Hugo, Noel Franco, and Carlos Chastre. "Stainless steel bonded to concrete: An experimental assessment using the DIC technique." International Journal of Concrete Structures and Materials. 12 (2018). AbstractWebsite

The durability performance of stainless steel makes it an interesting alternative for the structural strengthening of reinforced concrete. Like external steel plates or fibre reinforced polymers, stainless steel can be applied using externally bonded reinforcement (EBR) or the near surface mounted (NSM) bonding techniques. In the present work, a set of single-lap shear tests were carried out using the EBR and NSM bonding techniques. The evaluation of the performance of the bonding interfaces was done with the help of the digital image correlation (DIC) technique. The tests showed that the measurements gathered with DIC should be used with caution, since there is noise in the distribution of the slips and only the slips greater than one-tenth of a millimetre were fairly well predicted. For this reason, the slips had to be smoothed out to make it easier to determine the strains in the stainless steel and the bond stress transfer between materials, which helps to determine the bond–slip relationship of the interface. Moreover, the DIC technique allowed to identify all the states developed within the interface through the load–slip responses which were also closely predicted with other monitoring devices. Considering the NSM and the EBR samples with the same bonded lengths, it can be stated that the NSM system has the best performance due to their higher strength, being observed the rupture of the stainless steel in the samples with bond lengths of 200 and 300 mm. Associated with this higher strength, the NSM specimens had an effective bond length of 168 mm which is 71.5% of that obtained for the EBR specimens (235 mm). A trapezoidal and a power functions are the proposed shapes to describe the interfacial bond–slip relationships of the NSM and EBR systems, respectively, where the maximum bond stress in the former system is 1.8 times the maximum bond stress of the latter one.

Monteiro, C. M. B., F. D. Amaro, M. S. Sousa, M. Abdou-Ahmed, P. Amaro, F. Biraben, T. Chen, D. S. Covita, A. J. Dax, M. Diepold, L. M. P. Fernandes, B. Franke, S. Galtier, A. L. Gouvea, J. Götzfried, T. Graf, T. W. Hänsch, M. Hildebrandt, P. Indelicato, L. Julien, K. Kirch, A. Knecht, F. Kottmann, J. J. Krauth, Y. Liu, J. Machado, F. Mulhauser, B. Naar, T. Nebel, F. Nez, R. Pohl, J. P. Santos, J. M. F. dos Santos, K. Schuhmann, C. I. Szabo, D. Taqqu, J. F. C. A. Veloso, and A. Antognini. "{On the double peak structure of avalanche photodiode response to monoenergetic x-rays at various temperatures and bias voltages}." Journal of Instrumentation. 13 (2018): C01033. Abstract
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Mateus, Octávio, Eduardo Puértolas-Pascual, and Pedro M. Callapez. "A new eusuchian crocodylomorph from the Cenomanian (Late Cretaceous) of Portugal reveals novel implications on the origin of Crocodylia." Zoological Journal of the Linnean Society (2018). AbstractWebsite
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Cerdeira, Jorge Orestes, Tiago Monteiro-Henriques, Maria João Martins, Pedro C. Silva, Diogo Alagador, Aldina M. A. Franco, Manuel L. Campagnolo, Pedro Arsénio, Francisca C. Aguiar, and Mar Cabeza. "Revisiting niche fundamentals with Tukey depth." Methods in Ecology and Evolution (2018). AbstractWebsite
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Agnolin, Federico L., Octávio Mateus, Jesper Milàn, Marco Marzola, Oliver Wings, Jan Schulz Adolfssen, and Lars B. Clemmensen. "Ceratodus tunuensis, sp. nov., a new lungfish (Sarcopterygii, Dipnoi) from the Upper Triassic of central East Greenland." Journal of Vertebrate Paleontology (2018): e1439834. AbstractWebsite
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Revel, A., et al. "Strong Neutron Pairing in $\textrm{core}+4n$ Nuclei." Phys. Rev. Lett.. 120 (2018): 152504. AbstractWebsite
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LIDON, FERNANDO CEBOLA, KARLIANA OLIVEIRA, CARLOS GALHANO, Mauro Guerra, MARIA MANUELA RIBEIRO, JOÃO PELICA, INÊS PATACO, JOSÉ COCHICHO RAMALHO, ANTÓNIO EDUARDO LEITÃO, ANA SOFIA ALMEIDA, PAULA SCOTTI CAMPOS, Ana Ribeiro-Barros, ISABEL P. PAIS, Maria Manuela Silva, Maria Luisa Carvalho, Jose Paulo Santos, MARIA FERNANDA PESSOA, and FERNANDO HENRIQUE REBOREDO. "{SELENIUM BIOFORTIFICATION OF RICE THROUGH FOLIAR APPLICATION WITH SELENITE AND SELENATE}." Experimental Agriculture (2018): 1-15. Abstract

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Martins, David, Sueli T. M. Souza, Válter J. G. LUCIO, Carlos Chastre, and Luiz A. S. Souza. "Análise experimental de ligações pilar-pilar em torres treliçadas em concreto pré-moldado para suporte de geradores eólicos." Encontro Nacional Betão Estrutural - BE2018. LNEC, Lisboa, Portugal 2018. 10. Abstract

Com o crescente consumo de energia elétrica são cada vez mais os países que procuram fontes de energia renovável e limpa, entre elas a eólica. A quantidade de energia produzida é influenciada pela altura das torres, dimensões das pás e potência dos aerogeradores. Quanto maior for a elevação da turbina maiores são a velocidade e estabilidade dos ventos alcançados. A solução de torre treliçada em concreto armado pré-moldado idealizada por Lúcio e Chastre [2] permite a construção de torres altas e é competitiva em relação aos outros sistemas estruturais.As ligações têm uma importância fundamental no comportamento global das estruturas pré-moldadas. A viabilidade da ligação (fácil execução, baixo custo, comportamento/capacidade resistente) é preponderante na viabilização da construção destas torres.Até à data foram estudadas quatro ligações (S1, S2, S3 e S4), sendo neste artigo abordadas apenas as ligações do modelo S3 com junta de 3mm (barras salientes/bainhas corrugadas/selagem com grout) e do modelo S4 com junta de 50 mm (ligações aparafusadas produzidas comercialmente).Através dos resultados experimentais pode-se concluir que o mecanismo de rutura foi o mesmo nos dois modelos e que as soluções estudadas preenchem os requisitos para a sua utilização em estruturas pré-moldadas de concreto armado para suporte de aerogeradores.

Pacheco, João, Jorge de Brito, Carlos Chastre, and Luís Evangelista. "Avaliação dos resultados de resistência à compressão de betão pronto produzido em centrais portuguesas." Encontro Nacional Betão Estrutural - BE2018. LNEC, Lisboa, Portugal 2018. 10. Abstract

Este artigo avalia se, para especificações de betão correntes, a resistência à compressão de betão pronto é significativamente dependente da central que o produziu, bem como se a variabilidade entre amassaduras de uma determinada composição é dependente da classe de resistência especificada. É apresentado um parâmetro probabilístico que converte a resistência à compressão característica especificada para a resistência à compressão expectável em provetes de betão cúbicos em condições padronizadas.É feita uma análise estatística e probabilística dos resultados de ensaios de resistência à compressão aos 28 dias de betão pronto produzido em três centrais de betão portuguesas durante o ano de 2017. Após a avaliação da representatividade da base de dados analisada, é feito um estudo comparativo dos parâmetros estatísticos dos dados de produção das diferentes centrais e é avaliada a influência da classe de resistência à compressão do betão nestes parâmetros. Define-se e analisa-se um parâmetro probabilístico que converte a resistência à compressão especificada para a resistência potencial de betão, para cubos de 150 mm. Este parâmetro contribui para uma futura proposta de um modelo probabilístico, a ser utilizado em análises de fiabilidade, que converte a resistência à compressão especificada para a resistência à compressão de elementos de betão em obra.Quer a análise estatística dos ensaios de resistência à compressão, quer o parâmetro de conversão são comparados com os resultados de investigações internacionais na área, aferindo-se se a qualidade da produção de betão pronto nacional é semelhante à de outras regiões.

Biscaia, Hugo C., and Carlos Chastre. "Design method and verification of steel plate anchorages for FRP-to-concrete bonded interfaces." Composite Structures. 192 (2018): 52-66. AbstractWebsite

Concrete structures Externally Bonded Reinforced (EBR) with Fibre Reinforced Polymers (FRP) have been studied and used since the end of the last century. However, several issues need to be better studied in order to improve performance. The influence of size of anchorage plates used on Reinforced Concrete (RC) structures strengthened with EBR FRP composites, the external compressive stress to be applied on the anchorage plate and the numerical simulation of this region are some of the topics that need to be more carefully studied in order to clarify the performance of the FRP-to-concrete interface within the anchorage plate region. This study proposes a design methodology to estimate the amount of external compressive stress necessary to be applied on the anchorage plate of EBR systems with FRP composites, in order to avoid premature debonding. The external compressive stress imposed on the FRP composite is intended to simulate the effect produced by a mechanical anchorage system tightened to the EBR system. The results from the design proposal, when compared with the numerical ones, were efficient enough on the prediction of the bond strength improvement of FRP-to-concrete interfaces.

Biscaia, Hugo, and Carlos Chastre. "Degradation of EB-GFRP systems due to artificial aging conditions." XVI Portuguese Conference on Fracture (PCF2018). Universidade da Beira Interior, Covilhã, Portugal 2018. Abstract

The use of adhesively bonded joints between Fiber Reinforced Polymers (FRP) and concrete elements have been spread out in the past decades. However, due to their recent applications, the durability aspects related with these bonded joints requires the use of high safety factors which strongly restricts the mechanical capacity of the FRP composites. The experimental assessment of the degradation of FRP-to-concrete interfaces is an important task because it provides useful data that can be used to calibrate analytical or numerical models with the aim of helping on the correct understanding of the interfacial degradation. In this work, a new and simple interfacial bond-slip model that needs only one parameter to be experimentally defined is proposed. Compared to unaged Glass (G) FRP-to-concrete interfaces, the relative degradation of these bonded interfaces is studied after being subjected to: (i) salt fog cycles; (ii) wet-dry cycles; (iii) temperature cycles between -10ºC and +30ºC; and (iv) between +7.5ºC and +47.5ºC. The subsequent full debonding processes are predicted through an analytical model that takes into account the degradations experimentally determined from the tests.

Silva, Sara, Maria Falcão J. Silva, Paula Couto, and Fernando F. S. Pinho. "Reabilitação de um edifício de interesse público utilizando metodologias BIM." Congresso Nacional “Construção 2018”. FEUP. Porto 2018.
Biscaia, Hugo C., and Carlos Chastre Theoretical analysis of fracture in double overlap bonded joints with frp composites and thin steel plates. Vol. 190. Engineering Fracture Mechanics, 190., 2018. AbstractWebsite

The effective stress transfer between the fiber reinforced polymers (FRP) and the steel substrate is crucial for the successful retrofit of existing steel structures with FRP composites. However, there are no standard tests for FRP-to-steel interfaces, wherefore different test configurations have been used in recent years to assess the bond behaviour in these interfaces. The present study shows that the choice of test configuration is highly important and leads to different transfer stresses between the FRP and steel composites and consequently, has a direct influence on the strength of the bonded joint. Therefore, it is important to understand the debonding process that occurs in each test and avoid misinterpretations, erroneous analyses and dangerous characterizations of the interfacial behaviour of these interfaces. The current study presents a new analytical approach for the prediction of the debonding of FRP-to-steel interfaces when double-lap pull or double-strap tests are used.

Biscaia, Hugo Charrinho, Carlos Chastre, Cinderela Silva, and Noel Franco. "Mechanical response of anchored FRP bonded joints: A nonlinear analytical approach." Mechanics of Advanced Materials and Structures. 25 (2018): 238-252. AbstractWebsite

This article presents a nonlinear analytical solution for the prediction of the full-range debonding response of mechanically anchored, fiber-reinforced polymer (FRP) composites from the substrate. The nonlinear analytical approach predicts, for any monotonic loading history or bonded length, the relative displacements (or slips) between materials, the strains in the FRP composite, the bond stresses within the interface, and the stresses developed in the substrate. The load-slip responses of FRP-to-substrate interfaces with short and long bonded lengths are motives of analysis and discussion. The solutions obtained from the proposed approach are also compared with other experimental results found in the literature.

Ferrari, Arianna, Brandão A. Moniz, Christopher Coenen, Daniel Frank, Helge Torgersen, Leonhard Hennen, Ingrid Geesink, and Emilio Mordini Additive bio-manufacturing: 3D printing for medical recovery and human enhancement. Strasbourg: European Parliament, 2018. Abstracteprs_ida2018614571ann1_en.pdf

Additive manufacturing (commonly known as 3D printing or rapid prototyping) refers to processes used to produce parts in an additive manner by means of computer-aided design (CAD). While additive manufacturing is a technology that can be used in many different application areas, this project focuses on future trends in additive manufacturing (AM) aimed at improving biological functionality (bio-AM) and on its opportunities, barriers and challenges. The big advantage of this technique is that small batches can be produced more economically than with any other manufacturing process. Virtually any structure can be customized, which is particularly important in the healthcare sector. Possible applications include biological implants such as organs and tissues, nutrients, drugs and their transport mechanisms, equipment such as surgical knives and drilling guides, tissues for research, development and training, and personalized prostheses, supports and exoskeletons. Besides exploring such applications, the project will also systematically analyze potential "human enhancement" uses of AM technology and developments in the emerging do-it-yourself (DIY) cultures ("bio/body-hacking"; cyborgism; open source 3D printing movement).

In the first phase of the project, the technological state of the art will be analyzed, as will a wide variety of non-technical aspects, regulatory issues and future trends, also with a special focus on sociotechnical imaginaries (e.g., in science fiction), human enhancement and DIY cultures. This horizon scanning will be accomplished partly by means of expert and stakeholder interviews.

In the second phase, the project will use a variety of foresight and technology assessment methods and will carry out a 360° envisioning exercise with contributions by external experts, entailing an in-depth analysis of selected applications of bio-AM.

The project work will end with a scenario development phase in which the focus will be on likely outcomes of already emerging developments, though further-reaching future perspectives will be taken into account to a certain extent. Taken together, these scenarios will allow for both a broader understanding of the wide range of potential impacts of AM applications and a clearer picture of potential policy challenges relevant to the Members of the European Parliament.

Ropio, I., AC Baptista, JP Nobre, J. Correia, F. Belo, S. Taborda, BM Morais Faustino, J. P. Borges, A. Kovalenko, and I. Ferreira. "Cellulose paper functionalised with polypyrrole and poly (3, 4-ethylenedioxythiophene) for paper battery electrodes." 62 (2018): 530-535. Abstract
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Agnolin, Federico L., Octávio Mateus, Jesper Milàn, Marco Marzola, Oliver Wings, Jan Schulz Adolfssen, and Lars B. Clemmensen. "Ceratodus tunuensis, sp. nov., a new lungfish (Sarcopterygii, Dipnoi) from the Upper Triassic of central East Greenland." Journal of Vertebrate PaleontologyJournal of Vertebrate Paleontology (2018): e1439834. Abstractagnolin_et_al_2018_ceratodus_tunuensis_greenland.pdfWebsite

ABSTRACTThe fossil record of post-Paleozoic lungfishes in Greenland is currently restricted to a few brief reports of isolated and undetermined tooth plates coming from the uppermost Fleming Fjord Formation (late Norian) in Jameson Land, central East Greenland. Here, we describe Ceratodus tunuensis, sp. nov., a new dipnoan from a thin bed of calcareous lake mudstone from the ?rsted Dal Member of the Fleming Fjord Formation. The Ceratodus fossil record indicates that during the Late Triassic, this genus was restricted to the middle latitudes of the Northern Hemisphere. This record matches previous paleobiogeographical analyses and indicates that terrestrial biota during the Late Triassic was strongly influenced by paleolatitude.Citation for this article: Agnolin, F. L., O. Mateus, J. Milàn, M. Marzola, O. Wings, J. Schulz Adolfssen, and L. B. Clemmensen. 2018. Ceratodus tunuensis, sp. nov., a new lungfish (Sarcopterygii, Dipnoi) from the Upper Triassic of central East Greenland. Journal of Vertebrate Paleontology. DOI: 10.1080/02724634.2018.1439834.

Biscaia, Hugo, Rui Micaelo, Carlos Chastre, and João Cardoso. "Cyclic Loading Behaviour of Double Strap Bonded Joints with CFRP and Aluminium." Key Engineering Materials. 774 (2018): 36-41. AbstractWebsite

The adhesively bonded joints behaviour under cyclic loading is not yet well understood due to its inherent complexity. Numerical approaches appear, therefore, as the easiest way to simulate such mechanical behaviour. In this work, double strap bonded joints with Carbon Fibres Reinforced Polymers (CFRP) and aluminium are numerically simulated and subjected to a cyclic loading history. In the numerical simulation, the Distinct Element Method (DEM) is used and it is assumed cohesive bi-linear bond-slip models with local damage of the interface. The evaluation of the bonded joints under cyclic loading is made by comparing the results with those simulated with a monotonic loading.

Samhan-Arias, A. K., S. Fortalezas, C. M. Cordas, I. Moura, JJG Moura, and C. Gutierrez-Merino. "Cytochrome b5 reductase is the component from neuronal synaptic plasma membrane vesicles that generates superoxide anion upon stimulation by cytochrome c." Redox Biology. 15 (2018): 109-114. AbstractWebsite
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