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2016
Carvalho, Alda, Tiago A. N. Silva, Maria Amélia Ramos Loja, and Fábio Raimundo Damásio Assessing the influence of material and geometrical uncertainty on the mechanical behavior of FGM plates. Mechanics of Advanced Materials and Structures., 2016. Abstract
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Bahubalindruni, P.G.a, Tavares Barquinha Martins Fortunato V. c P. b. "Basic analog and digital circuits with a-IGZO TFTs." 2016 13th International Conference on Synthesis, Modeling, Analysis and Simulation Methods and Applications to Circuit Design, SMACD 2016. 2016. Abstract

This paper presents the characterization of fundamental analog and digital circuits with a-IGZO TFTs from measurements performed at normal ambient. The fundamental blocks considered in this work include digital logic gates, a low-power single stage high-gain amplifier with capcacitive bootstrapping and a level shifter/buffer. These circuits are important functional blocks in analog/Mixed signal IC design with oxide TFTs. Being fabricated at low temperature (< 200 °C), they can find potential applications in low-cost large-area flexible systems. © 2016 IEEE.

Cavalheiro, D., F. Moll, and S. Valtchev. "A battery-less, self-sustaining RF energy harvesting circuit with TFETs for ?w power applications." 14th IEEE International NEWCAS Conference, NEWCAS 2016 (2016). Abstract
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dos Santos, FA. "Buckling control using shape-memory alloy cables." Journal of Engineering Mechanics. 142 (2016). AbstractWebsite
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Loiola, Eliane Maria, Denis Silva da Silveira, João Araújo, and Ana Moreira. "Business Process Families: {A} Case Study in the Brazilian Public Sector." Proceedings of the CAiSE 2016 Industry Track co-located with 28th International Conference on Advanced Information Systems Engineering (CAiSE 2016), Ljubljana, Slovenia, June 13-17, 2016. 2016. Abstract
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Tschopp, Emanuel, and Octávio Mateus. "Case 3700 Diplodocus Marsh, 1878 (Dinosauria, Sauropoda): Proposed designation of D. carnegii Hatcher, 1901 as the type species." Bulletin of Zoological Nomenclature. 73 (2016): 17-24. Abstract

The purpose of this application, under Articles 78.1 and 81.1 of the Code, is to replace Diplodocus longus Marsh, 1878 as the type species of the sauropod dinosaur genus Diplodocus by the much better represented D. carnegii Hatcher, 1901, due to the undiagnosable state of the holotype of D. longus (YPM 1920, a partial tail and a chevron). The holotype of D. carnegii, CM 84, is a well-preserved and mostly articulated specimen. Casts of it are on display in various museums around the world, and the species has generally been used as the main reference for studies of comparative anatomy or phylogeny of the genus. Both species are known from the Upper Jurassic Morrison Formation of the western United States. The genus Diplodocus is the basis for the family-level taxa diplodocinae Marsh, 1884, diplodocidae Marsh, 1884, diplodocimorpha Marsh, 1884 (Calvo & Salgado, 1995) and diplodocoidea Marsh, 1884 (Upchurch, 1995). It is also a specifier of at least 10 phylogenetic clades. With the replacement of D. longus by D. carnegii as type species, Diplodocus could be preserved as a taxonomic name with generally accepted content. Taxonomic stability of the entire clade diplodocoidea, and the proposed definitions of several clades within Sauropoda, could be maintained.

c Nunes, D.a, Calmeiro Nandy Pinto Pimentel Barquinha Carvalho Walmsley Fortunato Martins T. R. a S. "Charging effects and surface potential variations of Cu-based nanowires." Thin Solid Films. 601 (2016): 45-53. AbstractWebsite

The present work reports charging effects and surface potential variations in pure copper, cuprous oxide and cupric oxide nanowires observed by electrostatic force microscopy (EFM) and Kelvin probe force microscopy (KPFM). The copper nanowires were produced by wet synthesis, oxidation into cuprous oxide nanowires was achieved through microwave irradiation and cupric oxide nanowires were obtained via furnace annealing in atmospheric conditions. Structural characterization of the nanowires was carried out by X-ray diffraction, scanning electron microscopy, transmission electron microscopy and energy dispersive X-ray spectroscopy. During the EFM experiments the electrostatic field of the positive probe charged negatively the Cu-based nanowires, which in turn polarized the SiO2 dielectric substrate. Both the probe/nanowire capacitance as well as the substrate polarization increased with the applied bias. Cu2O and CuO nanowires behaved distinctively during the EFM measurements in accordance with their band gap energies. The work functions (WF) of the Cu-based nanowires, obtained by KPFM measurements, yielded WFCuO > WFCu > WFCu2O. © 2015 Elsevier B.V.

Soares, Paula I. P., Ana Isabel Sousa, Jorge Carvalho Silva, Isabel M. M. Ferreira, Carlos M. M. Novo, and João Paulo Borges. "Chitosan-based nanoparticles as drug delivery systems for doxorubicin: Optimization and modelling." Carbohydrate polymers. 147 (2016): 304-312. Abstract
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André, Jorge, João Araújo, and Peter J. Cameron. "The classification of partition homogeneous groups with applications to semigroup theory." J. Algebra. 452 (2016): 288-310. AbstractWebsite
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André, Jorge, João Araújo, and Peter J. Cameron. "The classification of partition homogeneous groups with applications to semigroup theory." J. Algebra. 452 (2016): 288-310. AbstractWebsite
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Alagador, D., J. O. Cerdeira, and M. B. Araújo. "Climate change, species range shifts and dispersal corridors: an evaluation of spatial conservation models." Methods in Ecology and Evolution. 7 (2016): 853-866. Abstract
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Moldovan, O.a, Castro-Carranza Cerdeira Estrada Barquinha Martins Fortunato Miljakovic Iñiguez A. b A. c. "A compact model and direct parameters extraction techniques For amorphous gallium-indium-zinc-oxide thin film transistors." Solid-State Electronics. 126 (2016): 81-86. AbstractWebsite

An advanced compact and analytical drain current model for the amorphous gallium indium zinc oxide (GIZO) thin film transistors (TFTs) is proposed. Its output saturation behavior is improved by introducing a new asymptotic function. All model parameters were extracted using an adapted version of the Universal Method and Extraction Procedure (UMEM) applied for the first time for GIZO devices in a simple and direct form. We demonstrate the correct behavior of the model for negative VDS, a necessity for a complete compact model. In this way we prove the symmetry of source and drain electrodes and extend the range of applications to both signs of VDS. The model, in Verilog-A code, is implemented in Electronic Design Automation (EDA) tools, such as Smart Spice, and compared with measurements of TFTs. It describes accurately the experimental characteristics in the whole range of GIZO TFTs operation, making the model suitable for the design of circuits using these types of devices. © 2016 Elsevier Ltd

Souza, Eric, Silvia Abrahão, Ana Moreira, João Araújo, and Emilio Insfrán. "Comparing Value-Driven Methods: an Experiment Design." Proceedings of the Second International Workshop on Human Factors in Modeling co-located with {ACM/IEEE} 19th International Conference on Model Driven Engineering Languages and Systems {(MODELS} 2016), Saint Malo, France, October 4, 2016. 2016. 19-26. Abstract
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Cavalheiro, D., F. Moll, and S. Valtchev. "A comparison of TFET rectifiers for RF energy harvesting applications." Proceedings - 2016 IEEE International Power Electronics and Motion Control Conference, PEMC 2016 (2016): 14-19. Abstract
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Amaral, Paula, and Tiago Cardal Pais. "Compromise ratio with weighting functions in a Tabu Search multi-criteria approach to examination timetabling." Computers & Operations Research. 72 (2016): 160-174. Abstract
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Conceptual Modeling - 35th International Conference, {ER} 2016, Gifu, Japan, November 14-17, 2016, Proceedings. Eds. Isabelle Comyn -, Katsumi Tanaka, Il -, Shuichiro Yamamoto, and Motoshi Saeki. Vol. 9974., 2016. Abstract
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Marques, Susana CS, Paula I. P. Soares, Coro Echeverria, Maria H. Godinho, and João P. Borges. "Confinement of thermoresponsive microgels into fibres via colloidal electrospinning: experimental and statistical analysis." RSC Advances. 6.80 (2016): 76370-76380. Abstract
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Marques, Susana CS, Paula I. P. Soares, Coro Echeverria, Maria H. Godinho, and João P. Borges. "Confinement of thermoresponsive microgels into fibres via colloidal electrospinning: experimental and statistical analysis." RSC Advances. 6.80 (2016): 76370-76380. Abstract
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Dias, F. S., D. L. Miller, T. A. Marques, J. Marcelino, M. C. Caldeira, J. Orestes Cerdeira, and M. N. Bugalho. "Conservation zones promote oak regeneration and shrub diversity in certified Mediterranean oak woodlands." Biological Conservation. 195 (2016): 226-234. Abstract
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Chaves, M. M., J. M. Costa, O. Zarrouk, C. Pinheiro, C. M. Lopes, and JS Pereira. "Controlling stomatal aperture in semi-arid regions-The dilemma of saving water or being cool?" Plant Science. 251 (2016): 54-64. AbstractWebsite
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Mendes, M.J., Araújo Vicente Águas Ferreira Fortunato Martins A. A. H. "Design of optimized wave-optical spheroidal nanostructures for photonic-enhanced solar cells." Nano Energy. 26 (2016): 286-296. AbstractWebsite

The interaction of light with wavelength-sized photonic nanostructures is highly promising for light management applied to thin-film photovoltaics. Several light trapping effects come into play in the wave optics regime of such structures that crucially depend on the parameters of the photonic and absorbing elements. Thus, multi-parameter optimizations employing exact numerical models, as performed in this work, are essential to determine the maximum photocurrent enhancement that can be produced in solar cells.Generalized spheroidal geometries and high-index dielectric materials are considered here to model the design of the optical elements providing broadband absorption enhancement in planar silicon solar cells. The physical mechanisms responsible for such enhancement are schematized in a spectral diagram, providing a deeper understanding of the advantageous characteristics of the optimized geometries. The best structures, composed of TiO2 half-spheroids patterned on the cells' top surface, yield two times higher photocurrent (up to 32.5 mA/cm2 in 1.5 μm thick silicon layer) than the same devices without photonic schemes.These results set the state-of-the-art closer to the theoretical Lambertian limit. In addition, the considered light trapping designs are not affected by the traditional compromise between absorption enhancement versus current degradation by recombination, which is a key technological advantage. © 2016 Elsevier Ltd.

Mendes, Manuel J., Andreia Araújo, António Vicente, Hugo Águas, Isabel Ferreira, Elvira Fortunato, and Rodrigo Martins. "Design of optimized wave-optical spheroidal nanostructures for photonic-enhanced solar cells." Nano Energy. 26 (2016): 286-296. Abstract
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Mesherayakov, V., V. Voekov, V. Ivashkin, and S. Valtchev. "Designing the universal vector control system with relay current regulator principle for general purpose industrial AC motor drive control." Proceedings - 2016 IEEE International Power Electronics and Motion Control Conference, PEMC 2016 (2016): 680-685. Abstract
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Subramani, P., Sohel Rana, Bahman Ghiassi, Raul Fangueiro, Daniel V. Oliveira, Paulo B. Lourenco, and Jose Xavier. "Development and characterization of novel auxetic structures based on re-entrant hexagon design produced from braided composites." Composites Part B: Engineering. 93 (2016): 132-142. AbstractWebsite

Abstract This paper reports the first attempt of developing macro-scale auxetic structures based on re-entrant hexagon design from braided composite materials for civil engineering applications. Braided composite rods (BCRs) were produced and arranged as longitudinal and horizontal elements to produce three types of auxetic structures: (1) basic re-entrant hexagon structure, (2) basic structure modified by adding straight longitudinal elements and (3): structure-2 modified by changing structural angle. The influence of various material and structural parameters as well as structure type on Poisson's ratio and tensile properties was thoroughly investigated. The auxetic behaviour was found to strongly depend on the structural angle and straight elements, resulting in lower auxeticity with lower angles and in presence of straight elements. Material parameters influenced the auxetic behaviour to a lesser extent and a decrease in auxetic behaviour was noticed with increase in core fibre linear density and using stiffer fibres such as carbon. The reverse effect was observed in case of tensile strength and work of rupture. Among these structures, structure-3 exhibited good auxetic behaviour, balanced tensile properties, and high energy absorption capacity and their auxetic behaviour could be well predicted with the developed analytical model. Therefore, these novel structures present good potential for strengthening of civil structures.

Tschopp, E., and O. Mateus. "Diplodocus Marsh, 1878 (Dinosauria, Sauropoda): proposed designation of D. carnegii Hatcher, 1901 as the type species." Bulletin of Zoological Nomenclature. 73 (2016): 17-24. Abstract
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