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2016
Goswami, Sumita, Suman Nandy, Tomas R. Calmeiro, Rui Igreja, Rodrigo Martins, and Elvira Fortunato. "Stress Induced Mechano-electrical Writing-Reading of Polymer Film Powered by Contact Electrification Mechanism." Scientific Reports. 6 (2016). AbstractWebsite
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Santos-Silva, Teresa, Terao M, Romão MJ, Leimkühler S, Bolis M, Fratelli M, Coelho C, Santos-Silva T, and Garattini E. "Structure and function of mammalian aldehyde oxidases." (2016). AbstractWebsite
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Baikova, E. N., SS Valtchev, R. Melicio, A. Krusteva, and V. Fernão Pires. "Study of the electromagnetic interference generated by wireless power transfer systems." International Review of Electrical Engineering. 11 (2016): 526-534. Abstract
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Baikova, E. N., SS Valtchev, R. Melicio, V. F. Pires, A. Krusteva, and G. Gigov. "Study on electromagnetic emissions from wireless energy transfer." Proceedings - 2016 IEEE International Power Electronics and Motion Control Conference, PEMC 2016 (2016): 492-497. Abstract
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Bernardo, G. M. S., F. R. Damásio, T. A. N. Silva, and M. A. R. Loja A study on the structural behaviour of FGM plates static and free vibrations analyses. Vol. 136. Composite Structures, 136., 2016. Abstract
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Deuermeier, J., T. J. M. Bayer, H. Yanagi, A. Kiazadeh, R. Martins, A. Klein, and E. Fortunato. "Substrate reactivity as the origin of Fermi level pinning at the Cu2O/ALD-Al 2 O 3 interface." Materials Research Express. 3 (2016). Abstract
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d Deuermeier, J.a b, Bayer Yanagi Kiazadeh Martins Klein Fortunato T. J. M. b. "Substrate reactivity as the origin of Fermi level pinning at the Cu2O/ALD-Al2O3 interface." Materials Research Express. 3 (2016). AbstractWebsite

The reduction of aCu2O layer on copper by exposure toTMAduring the atomic layer deposition of Al2O3 has recently been reported. (Gharachorlou et al 2015 ACS Appl. Mater. Interfaces 7 16428-16439). The study presented here analyzes a similar process, leading to the reduction of a homogeneous Cu2O thin film, which allows for additional observations. Angle-resolved in situ X-ray photoelectron spectroscopy confirms the localization of metallic copper at the interface. The evaluation of binding energy shifts reveals the formation of aCu2O/Cu Schottky barrier, which gives rise to Fermi level pinning in Cu2O. An initial enhancement of the ALD growth per cycle (GPC) is only observed for bulk Cu2O samples and is thus related to lattice oxygen, originating from regions lying deeper than just the first few layers of the surface. The oxygen out-take from the substrate is limited to the first few cycles, which is found to be due to a saturated copper reduction, rather than the oxygen diffusion barrier of Al2O3. © 2016 IOP Publishing Ltd.

2015
Rahangdale, H. V., D. Mitra, M. Guerra, J. P. Santos, and S. Saha. "Subshell resolved inner shell ionization cross-sections of High Z elements by electron impact." Journal of Physics: Conference Series. 635 (2015): 052001-2. AbstractWebsite
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Mihaylov, Kaloyan, Stanimir Valtchev, and Rumen Arnaudov. "Smart microgrid sensorless load monitoring and management in {TN}-S and {TN}-C-S electrical networks." 2015 International Conference on Electrical Drives and Power Electronics ({EDPE}). Institute of Electrical {&} Electronics Engineers ({IEEE}), 2015. Abstract
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Mihaylov, Kaloyan, Stanimir Valtchev, and Rumen Arnaudov. "Sensorless load monitoring and management in electric power grid through energy harvesting." 2015 International Conference on Renewable Energy Research and Applications ({ICRERA}). Institute of Electrical {&} Electronics Engineers ({IEEE}), 2015. Abstract
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Farchi, Eitan, Robert M. Hierons, and João M. Lourenço. "Special issue on Testing, Analysis and Debugging of Concurrent Programs." Software Testing, Verification and Reliability. 25 (2015): 165-166. AbstractWebsite

This special issue concerns a range of issues related to the development of concurrent programs. This is an important topic, because many systems are now either multi-threaded or distributed, and it is well known that concurrency makes testing, analysis and debugging significantly more complicated. Essentially, the alternative interleavings of events can lead to different behaviours, and so any analysis, debugging or testing technique must consider these interleavings. The interest in this topic is reflected in the larger than normal issue, which contains five papers. The papers fall into three groups: we start with a paper on debugging, then have two on static analysis techniques and finally have two on testing. All papers were reviewed in the normal way.

Inacio, D., J. Murta Pina, P. Pereira, A. Pronto, M. Ventim Neves, and A. Alvarez. "Study of an axial flux disc motor with superconductor rotor." Compatibility and Power Electronics (CPE), 2015 9th International Conference on. Costa de Caparica, Portugal 2015. 488-493. Abstract

The integration of high temperature superconductors (HTS) in electrical machines potentially allows reduction in devices dimensions or performance improvement for the same active volume, when compared with their conventional ones. The use of polycrystalline HTS samples allows big bulk samples. An axial disc motor with HTS material or conventional aluminium in the rotor and conventional armature has been designed and developed. This paper describes simulations and laboratory experiments performed at liquid nitrogen temperature (77 K) in order to analyze the motor's behaviour and its electromechanical characteristics and to define an electric equivalent circuit that allows describing its operation. In order to evaluate the superconducting quality of the bulks and flux pinning phenomena, Hall probe mapping system was performed in order to define the field profiles at 77 K for different polar configurations. The analysis of the obtained results allows confirm the flux pinning phenomena, being the entire rotor magnetized and conclude that the motor with the HTS rotor behaves as a conventional hysteresis motor even though with a different nature, while the motor with aluminium rotor behaves as a conventional induction motor. In asynchronous regime, the HTS motor exhibits a constant torque, higher than the conventional aluminium one. For both cases, the developed torque is proportional to the poles pairs.

Lessa, Ivan, Glauco Carneiro, Miguel Monteiro, and Fernando Brito e Abreu. "Scaffolding MATLAB and Octave Software Comprehension Through Visualization." 27th International Conference on Software Engineering and Knowledge Engineering. Pittburgh, USA: IEEE, 2015. seke_20150619_final_with_doi.pdf
Santos, Lidia, Daniela Nunes, Tomas Calmeiro, Rita Branquinho, Daniela Salgueiro, Pedro Barquinha, Luis Pereira, Rodrigo Martins, and Elvira Fortunato. "Solvothermal Synthesis of Gallium-Indium-Zinc-Oxide Nanoparticles for Electrolyte-Gated Transistors." Acs Applied Materials & Interfaces. 7 (2015): 638-646. AbstractWebsite
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Guerra, M., P. Amaro, J. Machado, and J. P. Santos. "Single differential electron impact ionization cross sections in the binary-encounter- Bethe approximation for the low binding energy regime." Journal of Physics B: Atomic, Molecular and Optical Physics. 48 (2015): 1-9. AbstractWebsite

Journal of Physics B: Atomic, Molecular and Optical Physics, 48(2015) 185202. doi:10.1088/0953-4075/48/18/185202

Guerra, M., S. C. Pé-Leve Santos, A. M. E. Barroso, C. P. S. Fonseca, M. Eloy Cruz, P. Amaro, J. L. Figueirinhas, M. L. Carvalho, and J. P. Santos. "Spatially resolved determination of toxic trace elements in plants of Panasqueira mining region using micro X-ray fluorescence." Microscopy and Microanalysis. 21 (2015): 54-55. AbstractWebsite
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Tschopp, Emanuel, Octávio Mateus, and Roger B. J. Benson. "A specimen-level phylogenetic analysis and taxonomic revision of Diplodocidae (Dinosauria, Sauropoda)." PeerJ. 3 (2015): e857. Abstracttschopp_et_al_2015_brontosaurus_peerj-857.pdfWebsite

Diplodocidae are among the best known sauropod dinosaurs. Several species were described in the late 1800s or early 1900s from the Morrison Formation of North America. Since then, numerous additional specimens were recovered in the USA, Tanzania, Portugal, and Argentina, as well as possibly Spain, England, Georgia, Zimbabwe, and Asia. To date, the clade includes about 12 to 15 nominal species, some of them with questionable taxonomic status (e.g., ‘\textit{Diplodocus}’ \textit{hayi} or \textit{Dyslocosaurus polyonychius}), and ranging in age from Late Jurassic to Early Cretaceous. However, intrageneric relationships of the iconic, multi-species genera \textit{Apatosaurus} and \textit{Diplodocus} are still poorly known. The way to resolve this issue is a specimen-based phylogenetic analysis, which has been previously implemented for \textit{Apatosaurus}, but is here performed for the first time for the entire clade of Diplodocidae.The analysis includes 81 operational taxonomic units, 49 of which belong to Diplodocidae. The set of OTUs includes all name-bearing type specimens previously proposed to belong to Diplodocidae, alongside a set of relatively complete referred specimens, which increase the amount of anatomically overlapping material. Non-diplodocid outgroups were selected to test the affinities of potential diplodocid specimens that have subsequently been suggested to belong outside the clade. The specimens were scored for 477 morphological characters, representing one of the most extensive phylogenetic analyses of sauropod dinosaurs. Character states were figured and tables given in the case of numerical characters.The resulting cladogram recovers the classical arrangement of diplodocid relationships. Two numerical approaches were used to increase reproducibility in our taxonomic delimitation of species and genera. This resulted in the proposal that some species previously included in well-known genera like \textit{Apatosaurus} and \textit{Diplodocus} are generically distinct. Of particular note is that the famous genus \textit{Brontosaurus} is considered valid by our quantitative approach. Furthermore, “\textit{Diplodocus}” hayi represents a unique genus, which will herein be called \textit{Galeamopus} gen. nov. On the other hand, these numerical approaches imply synonymization of “\textit{Dinheirosaurus}” from the Late Jurassic of Portugal with the Morrison Formation genus \textit{Supersaurus}. Our use of a specimen-, rather than species-based approach increases knowledge of intraspecific and intrageneric variation in diplodocids, and the study demonstrates how specimen-based phylogenetic analysis is a valuable tool in sauropod taxonomy, and potentially in paleontology and taxonomy as a whole.

Santos, Lídia, Pawel Wojcik, Joana V. Pinto, Elamurugu Elangovan, Jaime Viegas, LuÍs Pereira, Rodrigo Martins, and Elvira Fortunato. "Structure and Morphologic Influence of WO3 Nanoparticles on the Electrochromic Performance of Dual-Phase a-WO3/WO3 Inkjet Printed Films." Advanced Electronic Materials (2015): n/a-n/a. AbstractWebsite

The optimization of tungsten trioxide (WO3) nanoparticles produced via hydrothermal synthesis for application in electrochromic (EC) devices is reported. The structure and morphology of the nanoparticles are controlled by changing the acidity of the aqueous solvent added to the sol-gel precursor (peroxopolytungstic acid) during synthesis. Orthorhombic hydrated WO3 nanorods or monoclinic WO3 nanoslabs are obtained when HCl is added, while synthesis only in aqueous medium results in a mixture of both types of polymorphs. Dual-phase thin films are processed by inkjet printing deposition of the nanoparticles in flexible polyethylene terephthalate substrate with indium tin oxide coating (ITO PET) followed by the deposition of the precursor solution. When compared with purely amorphous tungsten oxide films, the dual phase ones present higher optical densities and improved capacity, and cyclability stability. The best results, obtained for orthorhombic hydrated nanoparticles (ortho-WO3·0.33H2O), are due to its high surface area and improved conductivity. Additionally, the ex situ X-ray diffraction (XRD) lithiation studies show evidence of a higher distortion of the monoclinic when compared with the orthorhombic crystallographic structure, which contribute to the inferior EC performance. These results validate the use of inkjet printing deposition with low processing temperatures for EC dual-phase thin films containing optimized nanoparticles which are compatible with low-cost substrates.

Strganac, C., LL Jacobs, M. J. Polcyn, KM Ferguson, O. Mateus, Olímpio A. Gonçalves, M. - L. Morais, and T. da Silva Tavares. "Stable oxygen isotope chemostratigraphy and paleotemperature regime of mosasaurs at Bentiaba, Angola." Netherlands Journal of Geosciences. FirstView (2015): 1-7. Abstractstrganac_etal2015_stable_oxigen_isotopes.pdfWebsite

ABSTRACT Stable oxygen isotope values of inoceramid marine bivalve shells recovered from Bentiaba, Angola, are utilised as a proxy for paleotemperatures during the Late Cretaceous development of the African margin of the South Atlantic Ocean. The δ18O values derived from inoceramids show a long-term increase from –3.2‰ in the Late Turonian to values between –0.8 and –1.8‰ in the Late Campanian. Assuming a constant oceanic δ18O value, an ∼2‰ increase may reflect cooling of the shallow marine environment at Bentiaba by approximately 10°. Bentiaba values are offset by about +1‰ from published records for bathyal Inoceramus at Walvis Ridge. This offset in δ18O values suggests a temperature difference of ∼5° between coastal and deeper water offshore Angola. Cooler temperatures implied by the δ18O curve at Bentiaba coincide with the stratigraphic distribution of diverse marine amniotes, including mosasaurs, at Bentiaba.

de Melo, J. L. A., P. V. Leitão, J. Goes, and N. Paulino A simple class-D audio power amplifier using a passive CT ΣΔ modulator for medium quality sound systems. 22nd International Conference Mixed Design of Integrated Circuits & Systems (MIXDES’15). Torun, Poland: IEEE, 2015.
Mateus, João, Miguel Domingues, and João Costa Seco Sistema de Runtime para uma Linguagem Web Reativa. INForum 2015 - Actas do 7º Simpósio de Informática. Covilhã, 2015.
Amarante dos Santos, Filipe, Corneliu Cismasiu, and Chiara Bedon. "Smart glazed cable façade subjected to a blast loading." Proceedings of the Institution of Civil Engineers-Structures and Buildings (2015): 1-10. Abstract

This paper investigates the dynamic behaviour of cable-supported glazing façades
subjected to medium-level air blast loads. Preliminary numerical studies are carried-out in
SAP2000 by means of a geometrically refined and simplified lumped-mass finite-element
numerical model, in order to assess the major effects of the design blast load in the main
façade components. As shown, both the glass panels and the cable system are able to
properly accommodate the incoming impulsive loads, typically involving extreme ...

Rodríguez-Martínez, E. V., R. M. R. Cardoso, and A. D. Egídio dos Reis. "Some advances on the Erlang(n) dual risk model." ASTIN Bulletin. 45.1 (2015): 127-150.
Canteiro, Diogo, and Jácome Cunha. "SpreadsheetDoc: An Excel Add-in for Documenting Spreadsheets." Proceedings of the 6th National Symposium of Informatics (INForum’15). Covilhã, Portugal 2015. inforum2015.pdf
Karlovich, Alexei Yu. "The Stechkin inequality for Fourier multipliers on variable Lebesgue spaces." Mathematical Inequalities and Applications. 18.4 (2015): 1473-1481. Abstract

We prove the Stechkin inequality for Fourier multipliers on variable Lebesgue spaces under some natural assumptions on variable exponents.