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2016
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.
Correia, Isabel, Stefan Nickel, and Francisco Saldanha-da-Gama. "A Modeling Framework for Stochastic Multi-Period Capacitated Multiple Allocation Hub Location." ILS 2016 Conference - Information Systems, Logistics and Supply Chain. 2016. Abstract

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Conejero, José, Isabel Brito, Ana Moreira, Jácome Cunha, and João Araújo. "Modeling the Impact of UAVs in Sustainability." 5th International Workshop on Requirements Engineering for Sustainable Systems (RE4SuSy) @RE16. Beijing, China: IEEE CS, 2016. 2016-modeling-impact.pdf
Batista, AG, S. Najdi, D. M. Godinho, F. Serrano, M. D. Ortigueira, and R. T. Rato. "A Multichannel Time-Frequency and Multi-Wavelet Toolbox for Uterine Electromyography Processing and Visualisation." Computers in Biology and Medicine. 76.1 (2016): 178-191.
Souza, VGL, and Fernando AL. "Nanoparticles in food packaging: Biodegradability and potential migration to food—A review." Food Packaging and Shelf Life. 8 (2016): 63-70.
Seco, João Costa, Paulo Ferreira, and Hugo Lourenço Nested Data Manipulation in Distributed and Heterogeneous Environments -- extended version. Universidade Nova de Lisboa, 2016.tech-report.pdf
Myers, TS, O. Mateus, M. J. Polcyn, D. Vineyard, and LL Jacobs A new chelonioid turtle from the Paleocene of Cabinda, Angola. Annual Meeting of the Society of Vertebrate Paleontology. Journal of Vertebrate Paleontology, Program and Abstracts, 2016, 2016. Abstractmyers_etal_2016_chelonoid_angola_turtle_svp_abstract.pdf

We report a new chelonioid turtle on the basis of a nearly complete skull collected in lower Paleocene, shallow marine deposits, equivalent to the offshore Landana Formation, near the town of Landana in Cabinda Province, Angola. Chelonioid material previously reported from this locality is likely referable to this new taxon. The well-preserved skull is missing the left quadrate, squamosal, and prootic, both opisthotics, and the mandible. The skull possesses a rod-like basisphenoid rostrum, which is a synapomorphy of Chelonioidea, but it differs from other chelonioid skulls in that the contact between the parietal and squamosal is absent, and the posterior palatine foramen is present. Phylogenetic analysis recovers the new taxon as a basal chelonioid. The Paleocene– Eocene strata near Landana have produced a wealth of turtle fossils, including the holotype of the pleurodire Taphrosphys congolensis. A turtle humerus collected from the Landana locality differs morphologically from the humeri of chelonioids and Taphrosphys, indicating the presence of a third taxon. Chelonioid fossil material in the Landana assemblage is rare compared to the abundant fragmentary remains of Taphrosphys that are found throughout the stratigraphic section. This disparity in abundance suggests the new chelonioid taxon preferred open marine habitats, whereas Taphrosphys frequented nearshore environments.

Bastos, Ivan, Luis B. Oliveira, João Goes, João P. Oliveira, and Manuel M. Silva. "Noise cancelling LNA with gain enhancement by using double feedback." Integration, the VLSI Journal. 52 (2016): 309-315.
Fernandes, Vítor H., and Teresa M. Quinteiro. "A note on bilateral semidirect product decompositions of some monoids of order-preserving partial permutations." Bull. Korean Math. Soc.. 53.2 (2016): 495-506. AbstractWebsite

In this note we consider the monoid $PODI_n$ of all monotone partial permutations on $\{1,\ldots,n\}$ and its submonoids $DP_n$, $POI_n$ and $ODP_n$ of all partial isometries, of all order-preserving partial permutations and of all order-preserving partial isometries, respectively. We prove that both the monoids $POI_n$ and $ODP_n$ are quotients of bilateral semidirect products of two of their remarkable submonoids, namely of extensive and of co-extensive transformations. Moreover, we show that $PODI_n$ is a quotient of a semidirect product of $POI_n$ and the group $\mathcal{C}_2$ of order two and, analogously, $DP_n$ is a quotient of a semidirect product of $ODP_n$ and $\mathcal{C}_2$.

Oliveira, F. "A note on the existence of traveling-wave solutions to a Boussinesq system." Differential and Integral Equations. 29.1-2 (2016): 127-136.Website
Morgado, M. L., M. Rebelo, L. L. Ferrás, and N. Ford. "Numerical solution for diffusion equations with distributed order in time using a Chebyshev collocation method." Applied Numerical Mathematics . 114 (2016): 108-123.
Lopes, S., and H. Rocha O jogo como promotor da comunicação e aprendizagem matemática [Games to promote communication and mathematical learning]. XXVII SIEM. Porto, Portugal: APM, 2016. Abstract

Games are commonly appointed as a methodological tool capable of promoting students’ effective learning. In this context, this study intends to analyze the impact of mathematical discussions developed while
playing a polynomial game. Namely it intends to analyze the impact on the consolidation of mathematical concepts previously worked in the classroom and on the communications skills. Two case studies where developed involving 10th grade students. Data gathering was based on direct observation and an inquiry. The main conclusions suggest that the game encouraged the discussion about the mathematical contents and therefore promoted the development of the mathematical discourse. Besides that, it allowed a deeper apprehension of mathematical concepts, and the overcome of some difficulties.

Coelho, E., and H. Rocha O raciocínio dedutivo de alunos do 10.º ano de escolaridade [The deductive reasoning of students in the 10th grade]. XXVII SIEM. Porto, Portugal: APM, 2016. Abstract

Deductive reasoning, being central in mathematics, is also usually a source of difficulties for students, more used to the empirical approaches. In this study we focus on mathematical proof and we try to give attention to how this kind of reasoning is envisaged by the students, to the options they assume when asked to develop a deductive reasoning and to the factors affecting the implementation of this kind of reasoning. The study follows a qualitative and interpretative methodological approach, including the completion of two case studies of students of the 10th grade. Data were collected in work sessions and through interviews. The main findings point to a devaluation of mathematical proof and a strong preference for empirical approaches. Yet students show ability to develop different approaches. The preference for the mathematical subject and the attention given in class to the deduction work, appears to be relevant factors when considering the students' ability to develop a deductive reasoning when involved on a mathematical proof.

Biscaia, Hugo, Noel Franco, Ricardo Nunes, and Carlos Chastre. "Old suspended timber floors flexurally-strengthened with different structural materials." Key Engineering Materials. 713 (2016): 78-81. Abstract

The design of timber beams has strict limits when it comes to the Serviceability Limit States (SLS) either in short-term or in long-term deflections. In order to face this aspect efficiently, the increase of the cross section of the beams might be considered as a solution. However, the prohibitive increase of the costs associated to this solution or the change of the initial architecturedesign of the building, opens the opportunity to find new and more efficient solutions. In that way, the use of additional reinforcements to the timber beams may be seen as a promising solution because either new or old structures would keep always their original aesthetical aspect with no significant self-weight increase and improving their behaviour to short and long-term actions.Therefore, the current study is dedicated to the analysis of composite timber beams where Fiber Reinforcement Polymers (FRP), steel or stainless steel are used to improve the stiffness, strength and deflection behaviour of old suspended timber floors. An experimental program was conducted where old suspended timber floors reinforced with CFRP strips were subjected to 4-point bending tests. A simplify nonlinear numerical model was developed to simulate the bending behaviour of the specimens and several other cases with other reinforcement configurations and different structural materials were assumed. The numerical analysis herein presented also takes into account both Ultimate and Serviceability Limit States of the reinforced specimens.

Karlovich, Alexei Yu., Yuri I. Karlovich, and Amarino B. Lebre. "On a weighted singular integral operator with shifts and slowly oscillating data." Complex Analysis and Operator Theory. 10.6 (2016): 1101-1131. AbstractWebsite

Let \(\alpha,\beta\) be orientation-preserving diffeomorphism (shifts) of \(\mathbb{R}_+=(0,\infty)\) onto itself with the only fixed points \(0\) and \(\infty\) and \(U_\alpha,U_\beta\) be the isometric shift operators on \(L^p(\mathbb{R}_+)\) given by \(U_\alpha f=(\alpha')^{1/p}(f\circ\alpha)\), \(U_\beta f=(\beta')^{1/p}(f\circ\beta)\), and \(P_2^\pm=(I\pm S_2)/2\) where \[ (S_2 f)(t):=\frac{1}{\pi i}\int\limits_0^\infty \left(\frac{t}{\tau}\right)^{1/2-1/p}\frac{f(\tau)}{\tau-t}\,d\tau, \quad t\in\mathbb{R}_+, \]
is the weighted Cauchy singular integral operator. We prove that if \(\alpha',\beta'\) and \(c,d\) are continuous on \(\mathbb{R}_+\) and slowly oscillating at \(0\) and \(\ infty\), and \[ \limsup_{t\to s}|c(t)|<1,\quad \limsup_{t\to s}|d(t)|<1, \quad s\in\{0,\infty\}, \] then the operator \((I-cU_\alpha)P_2^++(I-dU_\beta)P_2^-\) is Fredholm on \(L^p(\mathbb{R}_+)\) and its index is equal to zero. Moreover, its regularizers are described.