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2014
Biscaia, Hugo C., Rui Micaelo, João Teixeira, and Carlos Chastre. "Numerical analysis of FRP anchorage zones with variable width." 67 (2014): 410-426. AbstractWebsite

AbstractThe use of Fibre Reinforced Polymers (FRP) has recently become widespread in the construction industry. However, some drawbacks related to premature debonding of the FRP composites from the bonded substrates have been identified. One of the solutions proposed is the implementation of mechanical anchorage systems. Although some design guidelines have been developed, the actual knowledge continues to be rather limited. Thus, designers and researchers have not yet achieved any consensus on the efficiency of any particular anchor device in delaying or preventing the premature debonding failure mode that can occur in Externally Bonded Reinforcement (EBR) systems. This paper studies the debonding phenomenon of FRP anchoring systems with a linear variable width, with a numerical analysis based on the Distinct Element Method (DEM). Combined systems with constant and variable width are also discussed. The FRP-to-parent material interfaces are modelled with a rigid-linear softening bond–slip law. The numerical results showed that it is possible to attain the FRP rupture force with a variable width solution. This solution is particularly attractive when the bonded length is shorter than the effective bonded length because the strength of the interface can be highly incremented.

Caeiro, Frederico Almeida Gião Gonçalves, and Ayana Maria Xavier Furtado Mateus. "An R implementation of several randomness tests." AIP Conference Proceedings. 2014. 531-534. Abstract

In many statistic methods, including distribution-free methods, we assume to work with random samples. In this note, we present randtests: an R package implementation of several nonparametric randomness tests. After a brief description of the tests included in the package, we present an application to real data sets in the field of Agricultural.In many statistic methods, including distribution-free methods, we assume to work with random samples. In this note, we present randtests: an R package implementation of several nonparametric randomness tests. After a brief description of the tests included in the package, we present an application to real data sets in the field of Agricultural.

Cardoso, T., P. Pereira, V. Fernao Pires, and J. F. Martins. "Power quality and long life education." Industrial Electronics (ISIE), 2014 IEEE 23rd International Symposium on. Istanbul - Turkey 2014. 2224-2228. Abstract

This paper presents a remote laboratory linked with mobile devices for real data analysis on the field of power quality. A global system was developed from the power quality analyzer into the human machine interface devoted to the m-learning system. This m-learning system is intended to be used in a long life learning perspective. The developed remote laboratory is a good opportunity for people, even without deep knowledge on the field, to learn power quality principles in an applied way. Since the system is based on real data, is a good approach to give trainees practical knowledge on the field.

Miguel, Catarina, Joana V. Pinto, Mark Clarke, and Maria J. Melo. "The alchemy of red mercury sulphide: The production of vermilion for medieval art." Dyes and Pigments. 102 (2014): 210-217. AbstractWebsite

Vermilion red, mercury sulphide (α-HgS), was one of the most important reds in art and its use as a pigment dates back to Antiquity. In medieval Europe, it could be mined as cinnabar, or produced as vermilion by heating mercury with sulphur. This work aims to study the production of synthetic vermilion as a medieval pigment and to confirm which was the source (mineral or artificial) of the reds used in Portuguese medieval illuminations. The production of synthetic vermilion was based on the process described in the Judaeo-Portuguese medieval treatise “The book on how to make colours”, using materials and technologies as close as possible to the medieval ones. The reaction mechanism was studied by following the heating process by X-ray diffraction, and it was possible to conclude that the transformation from black cubic β-HgS into red hexagonal α-HgS is a solid-state phase transition, occurring at 235 °C. This result is contrary to what published in technical art literature, in which this process is described as a sublimation. Moreover, Scanning Electron Microscopy evidenced a sinterization effect on the artificial vermilion, not found in medieval original samples nor in paints prepared with mineral cinnabar from Almadén (Spain). Red mercury sulphide, natural and synthetic, was then prepared as a parchment-glue paint and compared to proteinaceous red paints from 12th–13th century miniatures produced in important medieval monasteries, previously fully characterized by a multi-analytical approach (μ-Energy dispersive X-ray fluorescence, μ-Fourier Transform Infrared Spectroscopy, Raman microscopy). A comparative Electron probe microanalysis of the red paints point to a mineral provenance for medieval vermilion found in Portuguese illuminations.

Valério, P., A. M. Monge Soares, M. Fátima Araújo, R. J. C. Silva, E. Porfírio, and M. Serra. "Arsenical copper and bronze in Middle Bronze Age burial sites of southern Portugal: The first bronzes in Southwestern Iberia." Journal of Archaeological Science. 42.1 (2014): 68-80. AbstractWebsite
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Silva, Manuel A. G., Maria T. Cidade, Hugo Biscaia, and Rui Marreiros. "Composites and FRP-strengthened beams subjected to dry/wet and salt fog cycles." 26.12 (2014): 04014092. Abstract
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Pereira, Sónia, Alexandra Gonçalves, Nuno Correia, Joana Pinto, LuÍs Pereira, Rodrigo Martins, and Elvira Fortunato. "Electrochromic behavior of NiO thin films deposited by e-beam evaporation at room temperature." Solar Energy Materials and Solar Cells. 120, Part A (2014): 109-115. AbstractWebsite

In this work we report the role of thickness on electrochromic behavior of nickel oxide (NiO) films deposited by e-beam evaporation at room temperature on ITO-coated glass. The structure and morphology of films with thicknesses between 100 and 500 nm were analyzed and then correlated with electrochemical response and transmittance modulation when immersed in 0.5 M LiClO4–PC electrolyte. The NiO exhibits an anodic coloration, reaching for the thickest film a transmittance modulation of 66% between colored and bleached state, at 630 nm, with a color efficiency of 55 cm2 C−1. Very fast switch between states was obtained, where coloration and bleaching times are 3.6 s cm−2 and 1.4 s cm−2, respectively.

Acker, Arnold Van, Carlos Chastre, Barry Crisp, David Fernandez, Válter Lúcio, Kim S. Elliott, Simon Hughes, George Jones, Holger Karutz, Ronald Klein-Holte, Stef Maas, Marco Menegotto, Spyros Tsoukantas, and Pieter van der Zee fib Bulletin 74. Planning and design handbook on precast building structures. fib bulletin. Lausanne: International Federation for Structural Concrete (fib), 2014. AbstractWebsite

In 1994 fib Commission 6: Prefabrication edited a successful Planning and Design Handbook that ran to approximately 45,000 copies and was published in Spanish and German.Nearly 20 years later Bulletin 74 brings that first publication up to date. It offers a synthesis of the latest structural design knowledge about precast building structures against the background of 21st century technological innovations in materials, production and construction. With it, we hope to help architects and engineers achieve a full understanding of precast concrete building structures, the possibilities they offer and their specific design philosophy. It was principally written for non-seismic structures.

The handbook contains eleven chapters, each dealing with a specific aspect of precast building structures.
The first chapter of the handbook highlights best practice opportunities that will enable architects, design engineers and contractors to work together towards finding efficient solutions, which is something unique to precast concrete buildings.
The second chapter offers basic design recommendations that take into account the possibilities, restrictions and advantages of precast concrete, along with its detailing, manufacture, transport, erection and serviceability stages.
Chapter three describes the precast solutions for the most common types of buildings such as offices, sports stadiums, residential buildings, hotels, industrial warehouses and car parks. Different application possibilities are explored to teach us which types of precast units are commonly used in all those situations.
Chapter four covers the basic design principles and systems related to stability. Precast concrete structures should be designed according to a specific stability concept, unlike cast in-situ structures.
Chapter five discusses structural connections.
Chapters six to nine address the four most commonly used systems or subsystems of precast concrete in buildings, namely, portal and skeletal structures, wall-frame structures, floor and roof structures and architectural concrete facades.
In chapter ten the design and detailing of a number of specific construction details in precast elements are discussed, for example, supports, corbels, openings and cutouts in the units, special features related to the detailing of the reinforcement, and so forth.
Chapter eleven gives guidelines for the fire design of precast concrete structures. The handbook concludes with a list of references to good literature on precast concrete construction.

Dall'Agnol, L. T., C. M. Cordas, and JJG Moura. "Influence of respiratory substrate in carbon steel corrosion by a Sulphate Reducing Prokaryote model organism." Bioelectrochemistry. 97 (2014): 43-51. AbstractWebsite
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Veigas, Bruno, Rita Branquinho, Joana V. Pinto, Pawel J. Wojcik, Rodrigo Martins, Elvira Fortunato, and Pedro V. Baptista. "Ion sensing (EIS) real-time quantitative monitorization of isothermal DNA amplification." Biosensors and Bioelectronics (2014). Abstract
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Hendrickx, Christophe, Ricardo Araújo, and Octávio Mateus. "The nonavian theropod quadrate II: systematic usefulness, major trends and cladistic and phylogenetic morphometrics analyses." PeerJ PrePrints. 2 (2014): e380v2. AbstractWebsite

The skull-bone quadrate in nonavian theropods is very diverse morphologically alongside the disparity of the group as a whole. However this disparity has been underestimated for taxonomic purposes. In order to evaluate the phylogenetic potential and investigate the evolutionary transformations of the quadrate, we conducted a Catalano-Goloboff phylogenetic morphometric analysis as well as a cladistic analysis using 98 discrete quadrate related characters. The cladistic analysis provides a fully resolved tree mirroring to some degree the classification of nonavian theropods. The quadrate morphology by its own provides a wealth of data with strong phylogenetic signal and allows inference of major trends in the evolution of this bone. Important synapomorphies include: for Abelisauroidea, a lateral ramus extending to the ectocondyle; for Tetanurae, the absence of the lateral process; for Spinosauridae, a medial curvature of the ventral part of the pterygoid ramus occurring just above the mandibular articulation; for Avetheropoda, an anterior margin of the pterygoid flange formed by a roughly parabolic margin; and for Tyrannosauroidea, a semi-oval pterygoid flange shape in medial view. The Catalano-Goloboff phylogenetic morphometric analysis reveals two main morphotypes of the mandibular articulation of the quadrate linked to function. The first morphotype, characterized by an anteroposteriorly broad mandibular articulation with two ovoid/subcircular condyles roughly subequal in size, is found in Ceratosauria, Tyrannosauroidea and Oviraptorosauria. This morphotype allows a very weak displacement of the mandible laterally. The second morphotype is characterized by an elongate and anteroposteriorly narrow mandibular articulation and a long and parabolic/sigmoid ectocondyle. Present in Megalosauroidea, Carcharodontosauridae and Dromaeosauridae, this morphotype permits the lower jaw rami to be displaced laterally when the mouth opened.

Restani, Rita B., Joao Conde, Pedro V. Baptista, Maria Teresa Cidade, Ana M. Bragança, Jorge Morgado, Ilídio J. Correia, Ana Aguiar-Ricardo, and Vasco D. B. Bonifácio. "Polyurea dendrimer for efficient cytosolic siRNA delivery." 4.97 (2014): 54872-54878. Abstract
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Domingo, A., D. Specklin, V. Rosa, S. Mameri, V. Robert, and R. Welter. "Probing the influence of the ligands on the magnetism of dinuclear manganese, iron, and chromium complexes supported by aroylhydrazone." European Journal of Inorganic Chemistry.15 (2014): 2552-2560. AbstractWebsite
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Duarte, A. G., C. M. Cordas, JJG Moura, and I. Moura. "Steady-state kinetics with nitric oxide reductase (NOR): New considerations on substrate inhibition profile and catalytic mechanism." Biochimica et Biophysica Acta - Bioenergetics. 1837.3 (2014): 375-384. AbstractWebsite
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Passos, F., M. H. Fino, and E. R. Moreno. "Analytical Characterization of Variable Width Integrated Spiral Inductors." International Journal of Electronics and Telecommunications (2014): 7377.
de Melo, J. L. A., Querido F., Paulino N., and Goes J. A 0.4-V 410-nW opamp-less continuous-time ΣΔ modulator for biomedical applications. IEEE International Symposium on Circuits and Systems (ISCAS). Melbourne, Australia: IEEE, 2014.
Polcyn, M. J., LL Jacobs, C. Strganac, O. Mateus, TS Myers, S. May, R. Araújo, AS Schulp, and ML Morais. "Geological and paleoecological setting of a marine vertebrate bonebed from the Lower Maastrichtian at Bentiaba, Angola." Secondary Adaptation of Tetrapods to Aquatic Life. Washington DC, USA 2014.
Martins, R., and M. P. Amado. "Efficiency and energetic performance on the rehabilitation of residential buildings." 40th IAHS World Congress in Housing – Sustainable Housing Construction. 21 - ISBN: 978-989-98949-0-7. Funchal, Madeira - PT: IteCons - Universidade de Coimbra, 2014.
Mota, Bruna, Maria Isabel Gomes, and Ana P. Barbosa-Povoa. "Supply Chain Design towards sustainability: accounting for growth and jobs." Proceedings of the 8th International Conference on Foundations of Computer-Aided Process Design – FOCAPD 2014. Washington, USA 2014. 789-794. Abstract2014__motagomesbpovoa_focapd_va.pdf

Sustainable supply chain design is nowadays an important topic where not only economic and environmental aspects should be accounted for, but also social aspects are to be considered. A mathematical programming model was developed and a case-study was performed considering two different social indicators: one that prefers facility location in regions of lower GDP and the other in regions of higher unemployment rate. Results show that the outcome depends on the indicator used. However, for the case presented, minimum cost solution also corresponds to a good social solution regarding GDP, which could translate into economic incentives for the company.

Sniatala, P., M. Naumowicz, J. L. A. de Melo, and Goes J. "A hybrid current-mode passive second-order continuous-time ΣΔ modulator." 21st. International Conference on Mixed Design of Integrated Circuits and Systems (MIXDES). Poland: IEEE, 2014.
Biscaia, Hugo C., Rui Micaelo, João Teixeira, and Carlos Chastre. "Numerical analysis of FRP anchorage zones with variable width." Composites Part B: Engineering. 67 (2014): 410-426. AbstractWebsite

The use of Fibre Reinforced Polymers (FRP) has recently become widespread in the construction industry. However, some drawbacks related to premature debonding of the FRP composites from the bonded substrates have been identified. One of the solutions proposed is the implementation of mechanical anchorage systems. Although some design guidelines have been developed, the actual knowledge continues to be rather limited. Thus, designers and researchers have not yet achieved any consensus on the efficiency of any particular anchor device in delaying or preventing the premature debonding failure mode that can occur in Externally Bonded Reinforcement (EBR) systems. This paper studies the debonding phenomenon of FRP anchoring systems with a linear variable width, with a numerical analysis based on the Distinct Element Method (DEM). Combined systems with constant and variable width are also discussed. The FRP-to-parent material interfaces are modelled with a rigid-linear softening bond–slip law. The numerical results showed that it is possible to attain the FRP rupture force with a variable width solution. This solution is particularly attractive when the bonded length is shorter than the effective bonded length because the strength of the interface can be highly incremented.

Mateus, Octávio. "Comparison of modern and fossil Crocodylomorpha eggs and contribution to the oophylogeny of Amniota." Annual Meeting of the European Association of Vertebrate Palaeontologists. Vol. XII Annual Meeting of the European Association of Vertebrate Palaeontologists. 2014. 192. Abstract
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Mateus, Octávio Cracking dinosaur endothermy: paleophysiology unscrambled. Vol. NA., 2014. Abstract

The amniote eggshell functions as a respiratory structure adapted for the optimal transmission of respiratory gasses to and from the embryo according to its physiological requirements. Therefore amniotes with higher oxygen requirements, such as those that sustain higher metabolic rates, can be expected to have eggshells that can maintain a greater gas flux to and from the egg. Studies of extant amniotes have found that eggshells of reduced porosity impose a limit on the metabolic rate of the offspring. Here we show a highly significant relationship between metabolic rates and eggshell porosity in extant amniotes that predicts highly endothermic metabolic rates in dinosaurs. This study finds the eggshell porosity of extant endotherms to be significantly higher than that of extant ectotherms. Eggshell porosity values of dinosaurs are found to be significantly higherthan that of extant ectotherms, but not extant endotherms. Dinosaur eggshells are commonly preserved in the fossil record, and porosity may be readily identified and measured. This provides a simple tool to identify metabolic rates in extinct egg-laying tetrapods whose eggs possessed a mineralized shell