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2016
Biscaia, Hugo, Carlos Chastre, Isabel Borba, Cinderela Silva, and David Cruz. "Experimental evaluation of bonding between CFRP laminates and different structural materials." Journal of Composites for Construction. 20 (2016): 04015070. AbstractWebsite

This study presents an analysis of Carbon Fiber Reinforced Polymers (CFRP)-to-parent material interfaces based on 40 single-lap shear tests intended to highlight the strength of the interfaces under fracture mode II. Three different substrates are analyzed: timber;concrete and steel, using the same CFRP laminates and adhesive agent. The Externally Bonded Reinforcement (EBR) technique was used throughout the study. The results show that the CFRP-to-timber interfaces had the highest strength but also showed that these interfaces need a longer bonded length in order to reach maximum strength, i.e., CFRP-to-timber interfaces had the longest effective bond length. The local non-linear bond-slip curve of CFRP-to-concrete can be approximated to exponential curves, whereas the CFRP-to-timber or steel interfaces showed tri-linear and bi-linear bond-slip relations, respectively. Also, the CFRP-to-timber interfaces revealed the highest fracture energy.

Polcyn, M. J., N. Bardet, M. Amaghzaz, O. A. Gonçalves, E. Jourani, H. F. Kaddumi, J. Lindgren, O. Mateus, S. Meslouhf, ML Morais, X. Pereda-Suberbiola, AS Schulp, P. Vincent, and LL Jacobs An extremely derived plioplatecarpine mosasaur from the Maastrichtian of Africa and the Middle East. Vol. 16-20. 5th Triennial Mosasaur Meeting- a global perspective on Mesozoic marine amniotes, 16-20.May 16-20, 2016. Uppsala, Sweden: Museum of Evolutiom, Uppsala University., 2016. Abstractpolcyn_et_al_2016_extremely_derived_mosasaur.pdf

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Almeida, André, Válter Lúcio, and António Ramos. "Flat Slabs under Cyclic Reversed Horizontal Loads." 3rd NOVA-Yamaguchi International Seminar – Earthquake Resistant Structures. Caparica: FCT/UNL, 2016.
Biscaia, Hugo, Carlos Chastre, David Cruz, and Noel Franco. "Flexural Strengthening of Old Timber Floors with Laminated Carbon Fiber Reinforced Polymers." Journal of Composites for Construction (2016): 04016073. AbstractWebsite

A set of three old suspended timber floors were flexurally-strengthened with Carbon Fiber Reinforced Polymers (CFRP) strips in order to investigate the effectiveness of externally bonding FRP to their soffits. The specimens were from an old building and 740 mm-wide bands were transferred to the laboratory in order to be tested in a 4-point bending test. One specimen was tested with no strengthening system and the results obtained were used as reference values for comparison with the specimens those were externally bonded and reinforced (EBR) with CFRP strips. Two similar EBR systems were studied: (i) keeping both ends of the CFRP strips free of any restriction (traditional technique); and (ii) embedding both ends of the CFRP strips into the timber, thus providing a bonding anchorage of the strips (new technique). The installation of the new strengthening system comprises the opening of holes in the timber and the creation of a transition curve between the holes and the timber surface. This transition curve allows a smooth transition of the CFRP laminate between the hole and the timber surface, thus avoiding stress concentrations in this area. After the opening of the holes, the resin is applied inside the hole and on the beam surface, and then the CFRP laminate is mounted. The load-carrying capacity of the specimens, the rupture modes, the strains and bond stress distributions within the CFRP-to-timber interface are presented. A nonlinear numerical simulation of the specimens based on the mid-span cross-sectional equilibrium is also presented. The results showed that the use of the new strengthening system enhances the performance of the specimens when compared with the traditional strengthening system.

Kullberg, A. T. G., A. A. S. Lopes, J. P. B. Veiga, M. M. R. A. Lima, and R. C. C. Monteiro. "Formation and crystallization of zinc borosilicate glasses: Influence of the ZnO/B2O3." Journal of Non-Crystalline Solids. 441 (2016): 79-85. Abstract

© 2016 Elsevier B.V. All rights reserved.Different glasses based on the ZnO-B2O3-SiO2 system, with a ZnO content ≥ 60 mol{%} and a fixed SiO2 content (20 mol{%}), were synthesised using a melt-quenching method. Glass samples with zinc oxide concentrations as high as 65 mol{%} were prepared successfully without deteriorating the glass-forming ability. The glass samples were submitted to controlled heat-treatments, and the effect of the ZnO/B2O3 molar ratio on the formation of crystalline phases within the glass matrix was investigated by means of differential thermal analysis (DTA), X-ray diffraction (XRD) and scanning electron microscopy (SEM). DTA results indicated that the glass transition and the onset crystallization temperatures of the studied glasses tended to increase with the increment on the ZnO/B2O3 ratio. XRD data showed that the zinc binary crystalline phases, willemite (Zn2SiO4), a zinc orthosilicate, and zinc borate (Zn3B2O6) could be present in the crystallized glasses, depending on the heat-treatment conditions. The formation of willemite was promoted by an increasing ZnO/B2O3 ratio. Microstructural observations performed by SEM indicated that under controlled experimental parameters (glass composition, heat-treatment temperature and time) the precipitation of nanocrystals within the glass matrix can be achieved, resulting in transparent and translucent willemite glass-ceramics.

Śniatała, Paweł, Andrzej Handkiewicz, João Goes, Nuno Paulino, and João Pedro Oliveira Fully differential sigma-delta modulator structure for current-mode sensors. International Conference on Signals and Electronic Systems (ICSES’16). Krakow, Poland: IEEE, 2016.
Karlovich, Alexei Yu., Yuri I. Karlovich, and Amarino B. Lebre. "The generalized Cauchy index of some semi-almost periodic functions." Boletín de la Sociedad Matemática Mexicana. 22.2 (2016): 473-485. AbstractWebsite

We compute the generalized Cauchy index of some semi-almost periodic functions, which are important
in the study of the Fredholm index of singular integral operators with shifts and slowly oscillating data.

Oliveira, F., and H. Tavares. "Ground States for a nonlinear Schrödinger system with sublinear coupling terms." Advanced Nonlinear Studies. 16 (2016): 381-387.Website
Marzola, M., O. Mateus, O. Wings, N. Klein, J. Mìlan, and L.B.Clemmensen The herpetofauna from the Late Triassic of the Jameson Land Basin (East Greenland): review and updates. XIV EAVP Meeting. Haarlem, The Netherlands: XIV EAVP Meeting, Programme and Abstract Book, 2016.
Bahubalindrunia, Pydi Ganga, João Goes, and Pedro Barquinha A High-Gain, High-Speed Parametric Residue Amplifier for SAR-Assisted Pipeline ADCs. The 13th International Conference on Synthesis, Modeling, Analysis and Simulation Methods and Applications to Circuit Design (SMACD 2016). Lisbon, Portugal: IEEE, 2016.
and Ao Liu, Guoxia Liu, Huihui Zhu Byoungchul Shin Elvira Fortunato Rodrigo Martins Fukai Shan. "High-mobility p-type NiOx thin-film transistors processed at low temperatures with Al2O3 high-k dielectric." Journal of Materials Chemistry C. 4 (2016): 9438-9444. AbstractWebsite

Although there are a few research studies on solution-processed p-channel oxide thin-film transistors (TFTs), the strict fabrication conditions and the poor electrical properties have limited their applications in low-power complementary metal oxide semiconductor (CMOS) electronics. Here, the application of the polyol reduction method for processing p-type CuxO and NiOx channel layers and their implementation in TFT devices are reported. The optimized CuxO and NiOx TFTs were achieved at low annealing temperatures (∼300 °C) and exhibited decent electrical properties. Encouraged by the inspiring results obtained on SiO2/Si substrates, the TFT performance was further optimized by device engineering, employing high-k AlOx as the gate dielectric. The fully solution-processed NiOx/AlOx TFT could be operated at a low voltage of 3.5 V and exhibits a high hole mobility of around 25 cm2 V-1 s-1. Our work demonstrates the ability to grow high-quality p-type oxide films and devices via the polyol reduction method over large area substrates while at the same time it provides guidelines for further p-type oxide material and device improvements. © The Royal Society of Chemistry 2016.

MACHADO, José Saporiti, Sara Santos, Fernando F. PINHO, Fábio LUÍS, Ana Alves, Rita SIMÕES, and José C. RODRIGUES. "Impact of high moisture conditions on the serviceability performance of wood plastic composite decks." Materials and Design. 103. 122-131 .DOI: 10.1016/j.matdes.2016.04.030 (2016).
Lima, Catiele, José Barata, Pedro Fernandes, and Tiago Cardoso. "A Importância da Atuação do Arquiteto-Urbanista no Planejamento das Smart Cities." Pluris. Brasil 2016. Abstract

A importância do papel do Arquiteto-urbanista na caracterização dos conceitos e no planejamento das Smart Cities é um tema com muito por estudar e desenvolver. Este artigo faz uma aproximação a esta questão através de análise crítica com a seguinte abordagem: 1 - é feita uma descrição mais detalhada do porquê deste trabalho de investigação; 2 – apresenta-se uma contextualização da transição dos cenários; 3 - é levantada a problematização e a identificação de alguns motivos do “desenquadramento” da atuação do arquiteto-urbanista na cena; 4 – são discutidos aspectos e elencadas algumas características para “(re)enquadramento” dentro do cenário ideal, 5 – são analisados alguns casos de estudo; 6 - são tecidas conclusões. Este artigo mostra, portanto, o resultado deste estudo comparativo entre panorama atual e desejado, considerando este último como o cenário conceitual. É inicialmente caracterizada a situação atual através de levantamento da crítica especializada, depois é descrita a situação desejada tendo como base a análise de quatro casos de estudo; sendo dois de Smart Cities construídas a partir do zero e dois de cidade existentes que estão sendo transformadas em Smart Cities. Por fim, são identificados elementos que contribuem, na opinião dos autores, para o reassumir do papel do arquiteto-urbanista. Com este trabalho, foi possível, de uma forma sistematizada, estudar e suscitar ações deficitárias na atuação dos arquitetos-urbanistas, como também descortinar potenciais ações que podem induzir e reverter a transformação do cenário atual. Ficou claro que as necessidades intrínsecas ao novo modelo de cidade exigem ainda mais proposições criativas. O delinear das futuras cenas seria então ideal se os arquitetos-urbanistas retomassem posicionamento crítico propositivo e o utilizassem na solução que imagina novas e condizentes maneiras de habitar o espaço. O prelúdio já delineado convida então, os protagonistas na produção do espaço a alforriar-se da inércia, saindo da condição de espectadores e passando a condição de entendedores antecipados do cenário.

Anjos, Miguel F., and Manuel V. C. Vieira. "An improved two-stage optimization-based framework for unequal-areas facility layout." Optimization Letters. 10.7 (2016): 1379-1392.
Raposo, Miguel, Raquel Barateiro, Susana Martins, Tiago Cardoso, Miguel Palha, and José Barata. "Improving the Learning of Child Movements Through Games." International Conference on Serious Games, Interaction and Simulation. Springer, Cham, 2016. 15-22. Abstract

A Developmental Coordination Disorder can be identified when children show motor skills either below the expected levels considered adequate to their physical age or the opportunities provided for their learning. This problem affects four to six percent of school-age children, meaning that, from a very early stage of their life, they have several difficulties to adapt to the daily needs. In order to reduce the impact caused by this disorder, a team of therapists from “ – collected a wide range of exercises that allow the stimulus of several motor areas, including both the Gross and Fine Motor Skills. However, the application of this therapeutics is restricted to regular appointments. Since the motor stimulus, in order to be effective, need continuous application, it was found to be necessary to have a tool that in a practical and affordable way, fulfill this need. Therefore, the proposal presented in this article describes the creation of a systematic collection of such exercises in a friendly user manner for the children to be able to exercise elsewhere.

Mota, Bruna, Maria Isabel Gomes, Ana Carvalho, and Ana Paula Barbosa-povoa. "The influence of Corporate Social Responsibility on economic performance within supply chain planning." Computational Management Science: State of the Art 2014. Eds. Raquel J. Fonseca, Gerhard-Wilhelm Weber, and Joan Telhada. Springer, 2016. 151-156.2016_motagomescarvalhobpovoa_cms.pdf
Biscaia, Hugo, Manuel A. G. Silva, and Carlos Chastre. "Influence of external compressive stresses on the performance of GFRP-to-concrete interfaces subjected to aggressive environments: An experimental analysis." Journal of Composites for Construction . 20.2 (2016): 04015044. AbstractWebsite

Despite the fact that FRP composites are a reliable structural material with reasonable durability performance, the environment to which the strengthened structure is exposed can make the strengthening system vulnerable. In this study, the effectiveness of Externally Bonded Reinforcement (EBR) systems when external compressive stresses are applied to glass (G) FRP-to-concrete interfaces in several aggressive environments is analysed. The compressive stress imposed on the GFRP-to-concrete interface intends to simulate, for instance, the effect produced by a mechanical anchorage system applied to the EBR system. The design and the region to set those mechanical anchorage systems are not yet well understood and are mostly applied without really knowing how they will behave. This work shows an exhaustive experimental programme based on several double shear tests subjected to salt fog cycles, dry/wet cycles and two distinct temperature cycles: from -10ºC to +30ºC and +7.5ºC to +47.5ºC. The Mohr-Coulomb failure criterion was found to provide a good representation of the performance of the GFRP-to-concrete interface, and changes of cohesion and internal friction angle of those interfaces during the hours of exposure to the aggressive environments are reported.

Coutinho, M. L., A. Z. Miller, M. A. Rogerio-Candelera, J. Mirão, L. Cerqueira Alves, JP Veiga, H. Águas, S. Pereira, A. Lyubchyk, and MF Macedo. "An integrated approach for assessing the bioreceptivity of glazed tiles to phototrophic microorganisms." Biofouling. 32.3 (2016): 243-259. Abstract

© 2016 Taylor {&} Francis.A laboratory-based methodology was designed to assess the bioreceptivity of glazed tiles. The experimental set-up consisted of multiple steps: manufacturing of pristine and artificially aged glazed tiles, enrichment of phototrophic microorganisms, inoculation of phototrophs on glazed tiles, incubation under optimal conditions and quantification of biomass. In addition, tile intrinsic properties were assessed to determine which material properties contributed to tile bioreceptivity. Biofilm growth and biomass were appraised by digital image analysis, colorimetry and chlorophyll a analysis. SEM, micro-Raman and micro-particle induced X-ray emission analyses were carried out to investigate the biodeteriorating potential of phototrophic microorganisms on the glazed tiles. This practical and multidisciplinary approach showed that the accelerated colonization conditions allowed different types of tile bioreceptivity to be distinguished and to be related to precise characteristics of the material. Aged tiles showed higher bioreceptivity than pristine tiles due to their higher capillarity and permeability. Moreover, biophysical deterioration caused by chasmoendolithic growth was observed on colonized tile surfaces.

Morgado, M. L., and M. Rebelo. "Introducing graded meshes in the numerical approximation of distributed-order diffusion equations." NUMERICAL COMPUTATIONS: THEORY AND ALGORITHMS (NUMTA–2016). 2016.
Allaei, S. S., T. Diogo, and M. Rebelo. "The Jacobi Collocation Method for a Class of Nonlinear Volterra Integral Equations with Weakly Singular Kernel." Journal of Scientific Computing . 69.2 (2016): 673-695.
Mateus, O. Late Jurassic of Morrison Formation and Portugal tetrapods compared: a model to explain faunal exchange and similarity. Annual Meeting of the Society of Vertebrate Paleontology. Salt Late City: Journal of Vertebrate Paleontology, Program and Abstracts, 2016, 2016. Abstractmateus_2016_late_jurassic_morrison_svp_abstract.pdf

The precursor of the North Atlantic existed between the North American and Iberian blocks from the earliest Jurassic Hettangian and has been ever expanding since. By the Kimmeridgian and Tithonian, when much of the Morrison Fm rocks were deposited, the proto-Atlantic was more than 300 km wide at 27° paleolatitude between North America and Iberia. Macrovertebrate paleontology reveals a unique story to the isolation of Iberia and instead suggest a paleogeographic land connection between North American and Iberia. Torvosaurus, Allosaurus, Ceratosaurus, Stegosaurus, Supersaurus and others have a distribution restricted to Morrison Formation in North America and Lourinhã Formation in Portugal. A novel paleogeographic model is here suggested: (1) around the Middle–Late Jurassic transition there is a major palaeoceanographic and palaeoclimatic reorganization, coincidental to a major eustatic sea-level drop and uplift associated with the Callovian– Oxfordian Atlantic Regressive Event; (2) creating an ephemeral land bridge presenting a temporary opportunity for terrestrial gateways likely across the Flemish Cap and Galician Bank land masses, allowing large dinosaurian taxa to cross the northern proto-Atlantic in both directions; (3) finally, a Callovian–Oxfordian faunal exchange around the 163 Ma, through latest Kimmeridgian at 152 Ma (the age of equivalent genera in both Morrison and Portugal), is was an interval that allowed speciation, but retaining generic similarity of vertebrates. This model is consistent with the chronology and taxonomy required for speciation of the Iberian and American forms, exemplified by the coeval sister-taxa pairs Torvosaurus tanneri and T. gurneyi, Allosaurus fragilis and A. europaeus, or Supersaurus vivianae and S. lourinhanensis. While some of the smaller animals in the fauna show Morrison/Portugal affinities, most from Iberia have European or even Asian affinities. The larger-bodied fauna are more closely related to Morrison than to mainland Europe (except for dacentrurine stegosaurs). The body size differences and affinities of taxa across paleogeography is comparable to what is observed today across the Wallace Line. Migration may have also occurred in both directions. The closest relative of Torvosaurus is likely the European Bathonian Megalosaurus, thus the presence of the genus in North America represents a European migration. On other hand, Allosaurus and Supersaurus origins are consistent with a North American origin, representing an westto-east migration.

J. Afonso, D. Martins, Catarino Patrício Rocaboy Tirolien Bonfait I. R. A. T. "Liquid-gas cryogenic energy storage units operating at constant temperature." Applied Thermal Engineering. 95.25 (2016): 178-185.
Leal, A. A., A. Dionísio, M. A. S. Braga, and O. Mateus. "The long term preservation of Late Jurassic sandstone dinosaur footprints in a museum environment." International Journal of Conservation Science. 7.3 (2016): 627-646. AbstractWebsite

This study focuses on the assessment of the degradation processes occurring in three sandstone infills of fossilized Late Jurassic ornithopod tridactyl footprints, found in 2001 in a coastline cliff in Porto das Barcas (Lourinhã, Portugal) and exhibited in a museum display since 2004. These dinosaur footprints present nowadays severe decay phenomena compromising their physical integrity and are leading gradually to their loss of value. The deterioration patterns were recorded, a map of their distribution was prepared and several samples were collected both in the dinosaur footprints and in the coastline cliff. Different analytical procedures were applied such as XRD, FTIR, FESEM and Ion Chromatography. A microclimatic survey was also performed and air temperature and relative humidity was measured during eight months both indoor and also outdoor. The decay patterns observed are a combination intrinsic and extrinsic factors the stone material, namely swelling of clay minerals in the rock matrix (smectite and chlorite-smectite mixed-layer), presence of salts (mainly chlorides), application of past conservation treatments (poly(vinyl) acetate and epoxy resins) and with the museum's indoor thermohygrometric conditions (mainly non-stable hygrometric conditions). This scientific knowledge is therefore essential to the sustainable preservation of this paleontological heritage.

Rybarczyk, Y., and Zalakeviciute R. "Machine learning approach to forecasting urban pollution: a case study of Quito, Ecuador." IEEE ETCM. Guayaquil, Ecuador 2016.
Teixeira, Miguel Lima, Camilo Velez, Dian Li, and João Goes Micro-needle Based ECG – Glucose Painless MEMS Sensor with Analog Front End for Portable Devices. 8th IFIP WG 5.5/SOCOLNET Doctoral Conference on Computing, Electrical and Industrial Systems, DoCEIS’16. Caparica, Portugal: IFIP WG 5.5/SOCOLNET, 2016.