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2017
Cavalheiro, D., F. Moll, and S. Valtchev. "Insights into Tunnel FET-Based Charge Pumps and Rectifiers for Energy Harvesting Applications." IEEE Transactions on Very Large Scale Integration (VLSI) Systems. 25 (2017): 988-997. Abstract
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Angione, Giacomo, José Barbosa, Frederik Gosewehr, Paulo Leitão, Daniele Massa, João Matos, Ricardo Silva Peres, André Dionisio Rocha, and Jeffrey Wermann. "Integration and Deployment of a Distributed and Pluggable Industrial Architecture for the PERFoRM Project." 27th International Conference on Flexible Automation and Intelligent Manufacturing, FAIM2017. Vol. 11. 2017. 896-904. Abstract
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Santos-Silva, Teresa, Pessoa JC, Correia I, Chorna I, Cavaco I, Roy S, Kuznetsov ML, Ribeiro N, Justino G, Marques F, Silva TS, Santos M, Santos HM, Capelo JL, and Doutch J. "Interaction of VIVO(acac)2 with human serum transferrin and albumin." (2017). AbstractWebsite
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Duarte, Susana, and V. Cruz-Machado. "An investigation of lean and green supply chain in the Industry 4.0." Proceedings of the International Conference on Industrial Engineering and Operations Management. 2017 (2017): 255-265. Abstract

Industry 4.0 is the new paradigm of the fourth industrial revolution; it embodies a smart industry by applying advanced information and communication systems, and high technology. These advancements evolved and assisted the supply chain to become a more adaptive network creating new opportunities for supply chain competitiveness. Management paradigms as lean and green can develop improvements in the supply chain. The integrative lean and green approach eliminates non-value added activities and at the same time reduces environment impacts and risks throughout the supply chain operations. This study is motivated by the lack of evidence how the lean and green supply chain should evolve to work efficiently in Industry 4.0 environment. The purpose of this study is to investigate whether Industry 4.0 can support the implementation of the lean and green supply chain. Based on literature review, a conceptualization of the relations between Industry 4.0, supply chain management and lean and green paradigms is presented. This paper provides an understanding of how this new industrial revolution incorporated lean and green supply chain paradigms.

2016
Almeida, Graça, Fernando Melício, Hugo Biscaia, Carlos Chastre, and José Manuel Fonseca. "In-Plane Displacement and Strain Image Analysis." Computer-Aided Civil and Infrastructure Engineering. 31 (2016): 292-304. AbstractWebsite

Measurements in civil engineering load tests usually require considerable time and complex procedures. Therefore, measurements are usually constrained by the number of sensors resulting in a restricted monitored area. Image processing analysis is an alternative way that enables the measurement of the complete area of interest with a simple and effective setup. In this article photo sequences taken during load displacement tests were captured by a digital camera and processed with image correlation algorithms. Three different image processing algorithms were used with real images taken from tests using specimens of PVC and Plexiglas. The data obtained from the image processing algorithms were also compared with the data from physical sensors. A complete displacement and strain map were obtained. Results show that the accuracy of the measurements obtained by photogrammetry is equivalent to that from the physical sensors but with much less equipment and fewer setup requirements.

Pereira, Rui, Marco Couto, João Saraiva, Jácome Cunha, and João P. Fernandes. "The Influence of the Java Collection Framework on Overall Energy Consumption." 5th International Workshop on Green and Sustainable Software (ICSE 2016). 2016. –. Abstractgreens.pdf

This paper presents a detailed study of the energy consumption of the different Java Collection Framework (JFC) implementations. For each method of an implementation in this framework, we present its energy consumption when handling different amounts of data. Knowing the greenest methods for each implementation, we present an energy optimization approach for Java programs: based on calls to JFC methods in the source code of a program, we select the greenest implementation. Finally, we present preliminary results of optimizing a set of Java programs where we obtained 6.2% energy savings.

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.
Marques, Filipe J., and Florence Loingeville. "Improved near-exact distributions for the product of independent Generalized Gamma random variables." Computational Statistics & Data Analysis. 102 (2016): 55-66. Abstract
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Jorge, L. F. R., SS Valtchev, and R. Melicio. "Improving magnetic coupling for battery charging through 3D magnetic flux." Proceedings - 2016 IEEE International Power Electronics and Motion Control Conference, PEMC 2016 (2016): 291-297. Abstract
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c Kiazadeh, A.a b, Gomes Barquinha Martins Rovisco Pinto Martins Fortunato H. L. b P. "Improving positive and negative bias illumination stress stability in parylene passivated IGZO transistors." Applied Physics Letters. 109 (2016). AbstractWebsite

The impact of a parylene top-coating layer on the illumination and bias stress instabilities of indium-gallium-zinc oxide thin-film transistors (TFTs) is presented and discussed. The parylene coating substantially reduces the threshold voltage shift caused by continuous application of a gate bias and light exposure. The operational stability improves by 75%, and the light induced instability is reduced by 35%. The operational stability is quantified by fitting the threshold voltage shift with a stretched exponential model. Storage time as long as 7 months does not cause any measurable degradation on the electrical performance. It is proposed that parylene plays not only the role of an encapsulation layer but also of a defect passivation on the top semiconductor surface. It is also reported that depletion-mode TFTs are less sensitive to light induced instabilities. This is attributed to a defect neutralization process in the presence of free electrons. © 2016 Author(s).

Kiazadeh, A., H. L. Gomes, P. Barquinha, J. Martins, A. Rovisco, JV Pinto, R. Martins, and E. Fortunato. "Improving positive and negative bias illumination stress stability in parylene passivated IGZO transistors." Applied Physics Letters. 109 (2016). Abstract
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Martins, Marta, Pedro V. Baptista, Ana Soraia Mendo, Claudia Correia, Paula Videira, Antonio S. Rodrigues, J. Muthukumaran, Teresa Santos-Silva, Ana Silva, Fatima M. C. Guedes da Silva, Joana Gigante, Antonio Duarte, Malgorzata Gajewska, and Alexandra R. Fernandes. "In vitro and in vivo biological characterization of the anti-proliferative potential of a cyclic trinuclear organotin(IV) complex." Molecular Biosystems. 12 (2016): 1015-1023. Abstract
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Bahubalindruni, P.G.a, Kiazadeh Sacchetti Martins Rovisco Tavares Martins Fortunato Barquinha A. b A. b. "Influence of Channel Length Scaling on InGaZnO TFTs Characteristics: Unity Current-Gain Cutoff Frequency, Intrinsic Voltage-Gain, and On-Resistance." Journal of Display Technology. 12 (2016): 515-518. AbstractWebsite

This paper presents a study concerning the role of channel length scaling on IGZO TFT technology benchmark parameters, which are fabricated at temperatures not exceeding 180\, ^{\circ}C. The parameters under investigation are unity current-gain cutoff frequency, intrinsic voltage-gain, and on-resistance of the bottom-gate IGZO TFTs. As the channel length varies from 160 to 3 μm, the measured cutoff frequency increases from 163 {\rm kHz} to 111.5 {\rm MHz}, which is a superior value compared to the other competing low-temperature thin-film technologies, such as organic TFTs. On the other hand, for the same transistor dimensions, the measured intrinsic voltage-gain is changing from 165 to 5.3 and the on-resistance is decreasing from 1135.6 to 26.1 kØmega. TFTs with smaller channel length (3 μ m) have shown a highly negative turn-on voltage and hump in the subthreshold region, which can be attributed to short channel effects. The results obtained here, together with their interpretation based on device physics, provide crucial information for accurate IC design, enabling an adequate selection of device dimensions to maximize the performance of different circuit building blocks assuring the multifunctionality demanded by system-on-panel concepts. © 2005-2012 IEEE.

Bahubalindruni, P. G., A. Kiazadeh, A. Sacchetti, J. Martins, A. Rovisco, V. G. Tavares, R. Martins, E. Fortunato, and P. Barquinha. "Influence of Channel Length Scaling on InGaZnO TFTs Characteristics: Unity Current-Gain Cutoff Frequency, Intrinsic Voltage-Gain, and On-Resistance." Journal of Display Technology. 12 (2016): 515-518. Abstract
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Lyubchyk, A., Vicente Alves Catela Soule Mateus Mendes Águas Fortunato Martins A. P. U. "Influence of post-deposition annealing on electrical and optical properties of ZnO-based TCOs deposited at room temperature." Physica Status Solidi (A) Applications and Materials Science. 213 (2016): 2317-2328. AbstractWebsite

The post-deposition modification of ZnO-based transparent conductive oxides (TCOs) can be the key to produce thin films with optoelectronic properties similar to indium tin oxide (ITO), but at a much lower cost. Here, we present electro-optical results achieved for post-deposition annealing of Al–Zn–O (AZO), AZO:H, Ga–Zn–O:H (GZO:H), and Zn–O:H (ZNO:H) thin films deposited by RF sputtering at room temperature. These studies comprise results of thermal annealing at atmospheric pressure, vacuum, forming gas, H2 and Ar atmospheres, and H2 and Ar plasmas, which lead to significant enhancement of their electro-optical properties, which are correlated to morphological and structural improvements. The post-deposition annealing leads to an enhancement in resistivity above 40% for AZO, AZO:H, and GZO:H, reaching ρ ≈ 2.6–3.5 × 10−4 Ωcm, while ZnO:H showed a lower improvement of 13%. The averaged optical transmittance in the visible region is about 89% for the investigated TCOs. Such results match the properties of state-of-art ITO (ρ ≈ 10−4 Ωcm and transmittance in VIS range of 90%) employing much more earth-abundant materials. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim

Lyubchyk, Andriy, António Vicente, Pedro U. Alves, Bruno Catela, Bertrand Soule, Tiago Mateus, Manuel J. Mendes, Hugo Águas, Elvira Fortunato, and Rodrigo Martins. "Influence of post-deposition annealing on electrical and optical properties of ZnO-based TCOs deposited at room temperature." physica status solidi (a). 213 (2016): 2317-2328. Abstract
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Zubizarreta, C.a, G-Berasategui Ciarsolo Barriga Gaspar Martins Fortunato E. a I. a. "The influence of target erosion grade in the optoelectronic properties of AZO coatings growth by magnetron sputtering." Applied Surface Science. 380 (2016): 218-222. AbstractWebsite

Aluminum-doped zinc oxide (AZO) transparent conductor coating has emerged as promising substitute to tin-doped indium oxide (ITO) as electrode in optoelectronic applications such as photovoltaics or light emitting diodes (LEDs). Besides its high transmission in the visible spectral region and low resistivity, AZO presents a main advantage over other candidates such as graphene, carbon nanotubes or silver nanowires; it can be deposited using the technology industrially implemented to manufacture ITO layers, the magnetron sputtering (MS). This is a productive, reliable and green manufacturing technique. But to guarantee the robustness, reproducibility and reliability of the process there are still some issues to be addressed, such as the effect and control of the target state. In this paper a thorough study of the influence of the target erosion grade in developed coatings has been performed. AZO films have been deposited from a ceramic target by RF MS. Structure, optical transmittance and electrical properties of the produced coatings have been analyzed as function of the target erosion grade. No noticeable differences have been found neither in optoelectronic properties nor in the structure of the coatings, indicating that the RF MS is a stable and consistent process through the whole life of the target. © 2016 Elsevier B.V.

Araújo, A., Mendes Mateus Vicente Nunes Calmeiro Fortunato Águas Martins M. J. T. "Influence of the Substrate on the Morphology of Self-Assembled Silver Nanoparticles by Rapid Thermal Annealing." Journal of Physical Chemistry C. 120 (2016): 18235-18242. AbstractWebsite

Metal nanoparticles are of great interest for light trapping in photovoltaics. They are usually incorporated in the rear electrode of solar cells, providing strong light scattering at their surface plasmon resonances. In most cases, the nanoparticles are self-assembled by solid-state dewetting over a transparent conductive oxide (TCO) layer incorporated in the cell's rear electrode. Up to now, this process has been optimized mainly by tuning the thermal annealing parameters responsible for dewetting, or the thickness of the precursor metallic layer; but little attention has been paid to the influence of the underlying TCO layer properties on the morphology of the nanoparticles formed, which is the focus of the present article. This work investigates Ag nanoparticles structures produced on distinct surfaces by a simple, fast and highly reproducible method employing rapid thermal annealing. The results indicate that both the thermal conductivity and surface roughness of the TCO layer play a determinant role on the morphology of the nanostructures formed. This is of particular relevance, since we show in the study performed that the parasitic absorption of these Ag nanostructures is reduced, while the scattering is enhanced when the Ag nanostructures are formed on TCO layers with the highest conductivity and the lowest surface roughness (∼1 nm). These results unveil novel possibilities for the improvement of plasmonic nanostructures fabricated by thermal dewetting, via the careful adjustment of the physical properties of the underlying surface. © 2016 American Chemical Society.