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2014
Gonçalves, Sara, Hugo Lourenço, and Sérgio Silva Otimização automática de aplicações web usando templates client-side. INForum 2014 - Actas do 6º Simpósio de Informática., 2014.
Barreira, Gustavo, Ana S. D. Ferreira, Pedro Vidinha, Joaquim M. S. Cabral, José M. G. Martinho, João Carlos Lima, Eurico J. Cabrita, and Susana Barreiros. "Assessing diffusion in enzyme loaded sol–gel matrices." RSC Advances. 4 (2014): 25099-25105. AbstractWebsite

Pulsed field gradient spin echo high resolution magic angle spinning nuclear magnetic resonance spectroscopy is a powerful technique to characterize confined biosystems. We used this approach to assess the diffusion of solvent and reaction species within sol–gel matrices differing in enzyme loading.

Otelo-Cardoso, AR, V. Schwuchow, D. Rodrigues, E. J. Cabrita, S. Leimkühler, MJ Romão, and T. Santos-Silva. "Biochemical, Stabilization and Crystallization Studies on a Molecular Chaperone (PaoD) Involved in the Maturation of Molybdoenzymes." PLoS One. 9 (2014): e87295 . AbstractWebsite

Molybdenum and tungsten enzymes require specific chaperones for folding and cofactor insertion. PaoD is the chaperone of the periplasmic aldehyde oxidoreductase PaoABC. It is the last gene in the paoABCD operon in Escherichia coli and its presence is crucial for obtaining mature enzyme. PaoD is an unstable, 35 kDa, protein. Our biochemical studies showed that it is a dimer in solution with a tendency to form large aggregates, especially after freezing/thawing cycles. In order to improve stability, PaoD was thawed in the presence of two ionic liquids [C4mim]Cl and [C2OHmim]PF6 and no protein precipitation was observed. This allowed protein concentration and crystallization using polyethylene glycol or ammonium sulfate as precipitating agents. Saturation transfer difference – nuclear magnetic resonance (STD-NMR) experiments have also been performed in order to investigate the effect of the ionic liquids in the stabilization process, showing a clear interaction between the acidic ring protons of the cation and, most likely, negatively charged residues at the protein surface. DLS assays also show a reduction of the overall size of the protein aggregates in presence of ionic liquids. Furthermore, cofactor binding studies on PaoD showed that the protein is able to discriminate between molybdenum and tungsten bound to the molybdenum cofactor, since only a Mo-MPT form of the cofactor remained bound to PaoD.

Karlovich, Alexei Yu. "Boundedness of pseudodifferential operators on Banach function spaces." Operator Theory, Operator Algebras and Applications. Operator Theory: Advances and Applications, 242. Eds. Maria Amélia Bastos, Amarino Lebre, Stefan Samko, and Ilya M. Spitkovsky. Basel: Birkhäuser/Springer, 2014. 185-195. Abstract

We show that if the Hardy-Littlewood maximal operator is bounded on a separable Banach function space \(X(\mathbb{R}^n)\) and on its associate space \(X'(\mathbb{R}^n)\), then a pseudodifferential operator \(\operatorname{Op}(a)\) is bounded on \(X(\mathbb{R}^n)\) whenever the symbol \(a\) belongs to the Hörmander class \(S_{\rho,\delta}^{n(\rho-1)}\) with \(0<\rho\le 1\), \(0\le\delta<1\) or to the the Miyachi class \(S_{\rho,\delta}^{n(\rho-1)}(\varkappa,n)\) with \(0\le\delta\le\rho\le 1\), \(0\le\delta<1\), and \(\varkappa>0\). This result is applied to the case of variable Lebesgue spaces \(L^{p(\cdot)}(\mathbb{R}^n)\).

Leal, AS, O. Mateus, C. Tomás, and A. Dionísio. "Decay and conservation trial of Late Jurassic sandstone with dinosaur tracks in a museum environment (Museum of Lourinhã, Portugal)." Buletini i Shkencave Gjeologjike. 1.2014 (2014): 410. Abstractleal_et_al_2014_cbgassav1-_abstract_dinosaur_footprints__page_410.pdf

Abstract
Late Jurassic dinosaur footprints were found on a coastline cliff in Lourinhã, Porto das Barcas, Lagido do Forno (coordinate 39°14.178’N, 9°20.397’W, Portugal) in June 2001. The locality is characterized by steep cliffs with high slopes that are composed of gray and red sandstones/ siltstones. The location belongs to the successions of Lusitanian Basin representing the Porto Novo Member of the Lourinhã Formation. Three natural infills of tridactyl tracks, possibly ascribed to ornithopod, a bipedal herbivore were found, representing a left foot movement, a right and a left one, respectively. Footprints are 300- 400mm wide and have a height of 330-360mm. The footprints are characterized by round fingers, which are elongated due to some degradation/ erosion. The footprints were collected from the field in 2001 and subsequently cleaned, consolidated and glued in the laboratory of the Museum of Lourinhã before being exhibited in a museum display. Stone matrix was removed and a consolidation product was applied, probably a polyvinyl acetate. The footprint with broken central digit was glued with an epoxy resin, Araldite. Both applied products were confirmed by analysis of μ- FTIR and both presented colour change and detachment surface problems. The footprints have been exposed in the palaeontology hall of the Museum of Lourinhã, Portugal from 2004 without climate controlling. These trace fossils form an important part of the palaeontological collection of Late Jurassic vertebrate fossils from Lourinhã Formation. Presently, it is considered a unique heritage in danger of disappearing due to high decay level of disaggregation of its geological structure. The footprints display several pathologies, such as “Blistering”, “Powdering”, “Exfoliation”’ as well as “Dirt”, “Fracture”’, “Inscriptions”, “Consolidants” and “Adhesives” and are now in very poor conditions. Laboratorial analysed were made to evaluate the presence of salts. Moreover a microclimatic study was conducted inside the museum to evaluate the influence of thermo-hygrometric parameters on the decay processes. The future interventions will depend on the results of consolidation trials that are currently under progress by using stone samples taken from the same layer and location from Porto das Barcas applying different commercial consolidation products.

Leal, Sofia, Octávio Mateus, Carla Tomás, and Amélia Dionisio Degradation processes and consolidation of Late Jurassic sandstone dinosaur tracks in museum environment (Museum of Lourinhã, Portugal). EGU General Assembly 2014 - Geophysical Research Abstracts., 2014.leal_et_al_2014_tracks_lab_egu2014-9026-1.pdf
Garde, F., A. Lenoir, A. Scognamiglio, D. Aelenei, D. Waldren, HN Rostvik, J. Ayoub, L. Aelenei, M. Donn, M. Tardif, and others. "Design of net zero energy buildings: Feedback from international projects." Energy Procedia. 61 (2014): 995-998. Abstract

The International Energy Agency (IEA), through the Solar Heating and Cooling programme (SHC) Task 40 and the Energy Conservation in Buildings and Community Systems programme (ECBCS, now named EBC) Annex 52, works towards developing a common understanding and setting up the basis for an international definition framework for Net Zero Energy Buildings (Net ZEBs). One of the subtasks of this programme?SubTaskC focuses benchmarking the Net ZEBs around the world to identify the innovative solutions sets that makes up this new type of building. This paper presents an overview of the work conducted by the participants of Subtask C and of Zero Energy Building projects that have been identified.

Seabra, J., Rybarczyk, Y., Batista, A., Rybarczyk, P., Lebret, M.C., and Vernay D. "Development of a wearable monitoring system for service dogs." IEEE Roman’14, Workshop on Wearable Technology and Human-Wearable Robot Interaction. Edinburgh, UK 2014.
Ramos, Pinho A., Válter J. G. Lúcio, and Duarte M. V. Faria. "The effect of the vertical component of prestress forces on the punching strength of flat slabs." Engineering Structures. 76 (2014): 90-98. Abstract

The use of prestress in flat slabs is a common solution, mainly because it allows larger spans and thinner slabs. Nevertheless, smaller thicknesses near the slab-column connections, along with the superposition of high shear and flexural stresses, arise the question of the slab capacity to resist punching. The punching failure results from the superposition of shear and flexural stresses near the column, and is associated to the formation of a pyramidal plug of concrete which punches through the slab. It is a local and brittle failure. The use of prestress can increase the punching capacity of flat slabs-column connections.This work presents the experimental analysis of flat slab specimens with tendons under punching. Nine slabs were tested using unbonded prestress with high strength steel tendons. The influences on the punching capacity of the vertical component of the prestress forces resulting from inclined tendons near the column and their distance to the column are analysed. The in-plane compression force due to prestress was not applied to the slabs, in order to evaluate only the deviation force influence. This work aims to improve the understanding of the behaviour of prestressed flat slabs under punching load in order to properly evaluate the punching resistance of this kind of structures. The experimental punching loads are compared with the provisions of EC2, ACI 318-11 and MC2010. © 2014 Elsevier Ltd.

Larrinaga, Pello, Carlos Chastre, Hugo C. Biscaia, and José T. San-José. "Experimental and Numerical Modelling of Basalt Textile Reinforced Mortar Behavior Under Uniaxial Tensile Stress." Materials & Design. 55.March (2014): 66-74. AbstractWebsite

During the last years several projects and studies have improved the knowledge about Textile Reinforced Mortar (TRM) technology. TRM has already been used in strengthening masonry and reinforced concrete structural elements such as walls, arches, columns and beams. This material is presented as a real alternative to the use of fibre-reinforced polymers (FRP) in situations where these composites have presented some drawbacks or their use is banned. Textile Reinforced Mortar show a complex mechanical behaviour derived from the heterogeneity of the constituent materials. This paper aims to deepen the knowledge of this composite material in terms of tensile behaviour. Following this scope, this paper presents an experimental campaign focused on thirty one TRM specimens reinforced with four different reinforcing ratios. The results are analysed and contrasted with two distinct models. i) the Aveston-Cooper-Kelly theory (ACK) which is based on a tri-linear analytical approach; and ii) a nonlinear numerical simulation with a 3D Finite Element code. The Finite Element Analysis (FEA) of the TRM tensile tests also showed no significant dependence on the basalt-to-mortar interface, i.e., the choice of a bond-slip curve in order to reproduce the bond stresses and slippages along the interface is irrelevant and it can be simply considered as rigid interface.

Karlovich, Alexei Yu., Yuri I. Karlovich, and Amarino B. Lebre. "Fredholmness and index of simplest singular integral operators with two slowly oscillating shifts." Operators and Matrices. 8.4 (2014): 935-955. AbstractWebsite

Let \(\alpha\) and \(\beta\) be orientation-preserving diffeomorphisms (shifts) of \(\mathbb{R}_+=(0,\infty)\) onto itself with the only fixed points \(0\) and \(\infty\), where the derivatives \(\alpha'\) and \(\beta'\) may have discontinuities of slowly oscillating type at \(0\) and \(\infty\). For \(p\in(1,\infty)\), we consider the weighted shift operators \(U_\alpha\) and \(U_\beta\) given on the Lebesgue space \(L^p(\mathbb{R}_+)\) by \(U_\alpha f=(\alpha')^{1/p}(f\circ\alpha)\) and \(U_\beta f= (\beta')^{1/p}(f\circ\beta)\). We apply the theory of Mellin pseudodifferential operators with symbols of limited smoothness to study the simplest singular integral operators with two shifts \(A_{ij}=U_\alpha^i P_++U_\beta^j P_-\) on the space \(L^p(\mathbb{R}_+)\), where \(P_\pm=(I\pm S)/2\) are operators associated to the Cauchy singular integral operator \(S\), and \(i,j\in\mathbb{Z}\). We prove that all \(A_{ij}\) are Fredholm operators on \(L^p(\mathbb{R}_+)\) and have zero indices.

Carvalho, T., V. Augusto, A. Rocha, N. M. T. Lourenco, N. T. Correia, S. Barreiros, P. Vidinha, E. J. Cabrita, and M. Dionisio. "Ion Jelly Conductive Properties Using Dicyanamide-Based Ionic Liquids." Journal of Physical Chemistry B. 118.31 (2014): 9445-59. AbstractWebsite

The thermal behavior and transport properties of several ion jellys (IJs), a composite that results from the combination of gelatin with an ionic liquid (IL), were investigated by dielectric relaxation spectroscopy (DRS), differential scanning calorimetry (DSC), and pulsed field gradient nuclear magnetic resonance spectroscopy (PFG NMR). Four different ILs containing the dicyanamide anion were used: 1-butyl-3-methylimidazolium dicyanamide (BMIMDCA), 1-ethyl-3-methylimidazolium dicyanamide (EMIMDCA), 1-butyl-1-methylpyrrolidinium dicyanamide (BMPyrDCA), and 1-butylpyridinium dicyanamide (BPyDCA); the bulk ILs were also investigated for comparison. A glass transition was detected by DSC for all materials, ILs and IJs, allowing them to be classified as glass formers. Additionally, an increase in the glass transition temperature upon dehydration was observed with a greater extent for IJs, attributed to a greater hindrance imposed by the gelatin matrix after water removal, rendering the IL less mobile. While crystallization is observed for some ILs with negligible water content, it was never detected for any IJ upon thermal cycling, which persist always as fully amorphous materials. From DRS measurements, conductivity and diffusion coefficients for both cations (D+) and anions (D–) were extracted. D+ values obtained by DRS reveal excellent agreement with those obtained from PFG NMR direct measurements, obeying the same VFTH equation over a large temperature range (ΔT ≈ 150 K) within which D+ varies around 10 decades. At temperatures close to room temperature, the IJs exhibit D values comparable to the most hydrated (9%) ILs. The IJ derived from EMIMDCA possesses the highest conductivity and diffusion coefficient, respectively, 10–2 S·cm–1 and 10–10 m2·s–1. For BMPyrDCA the relaxational behavior was analyzed through the complex permittivity and modulus formalism allowing the assignment of the detected secondary relaxation to a Johari–Goldstein process. Besides the relevant information on the more fundamental nature providing physicochemical details on ILs behavior, new doorways are opened for practical applications by using IJ as a strategy to produce novel and stable electrolytes for different electrochemical devices.

Liu, H., and Teresa Sousa. "Monochromatic K_r-Decompositions of Graphs." Journal of Graph Theory. 76 (2014): 89-100. Abstractmono-clique-preprint.pdf

Given graphs G and H, and a coloring of the edges of G with k colors, a monochromatic H-decomposition of G is a partition of the edge set of G such that each part is either a single edge or forms a monochromatic graph isomorphic to H. Let f_{k}(n,H) be the smallest number t such that any graph G of order n and any coloring of its edges with k colors, admits a monochromatic H-decomposition with at most t parts. Here we study the function f_{k}(n,K_r) for k≥ 2 and r≥ 3.

Vera-Cruz, Rui, and Ana Cruz Lopes. "O Turismo Cultural e o Património." Anuário do Património 2 - Boas Práticas de Conservação e Restauro. Lisbon: Canto Redondo, 2014. 260-271.
Fiedor, Jan, Zdeněk Letko, João Lourenço, and Tomáš Vojnar. "On Monitoring C/C++ Transactional Memory Programs." Mathematical and Engineering Methods in Computer Science. Eds. Petr Hliněný, Zdeněk Dvořák, Jiří Jaroš, Jan Kofroň, Jan Kořenek, Petr Matula, and Karel Pala. Vol. 8934. Lecture Notes in Computer Science, 8934. Springer International Publishing, 2014. 73-87. Abstractmemics14-monitoring-tm.pdf

Transactional memory (TM) is an increasingly popular technique for synchronising threads in multi-threaded programs. To address both correctness and performance-related issues of TM programs, one needs to monitor and analyse their execution. However, monitoring concurrent programs (including TM programs) may have a non-negligible impact on their behaviour, which may hamper the objectives of the intended analysis. In this paper, we propose several approaches for monitoring TM programs and study their impact on the behaviour of the monitored programs. The considered approaches range from specialised lightweight monitoring to generic heavyweight monitoring. The implemented monitoring tools are publicly available to the scientific community, and the implementation techniques used for lightweight monitoring of TM programs may be used as an inspiration for developing other specialised lightweight monitors.

Karlovich, Alexei Yu., Yuri I. Karlovich, and Amarino B. Lebre. "On regularization of Mellin PDO's with slowly oscillating symbols of limited smoothness." Communications in Mathematical Analysis. 17.2 (2014): 189-208. AbstractWebsite

We study Mellin pseudodifferential operators (shortly, Mellin PDO's) with symbols in the algebra \(\widetilde{\mathcal{E}}(\mathbb{R}_+,V(\mathbb{R}))\) of slowly oscillating functions of limited smoothness introduced in [K09]. We show that if \(\mathfrak{a}\in\widetilde{\mathcal{E}}(\mathbb{R}_+,V(\mathbb{R}))\) does not degenerate on the ``boundary" of \(\mathbb{R}_+\times\mathbb{R}\) in a certain sense, then the Mellin PDO \(\operatorname{Op}(\mathfrak{a})\) is Fredholm on the space \(L^p\) for \(p\in(1,\infty)\) and each its regularizer is of the form \(\operatorname{Op}(\mathfrak{b})+K\) where \(K\) is a compact operator on \(L^p\) and \(\mathfrak{b}\) is a certain explicitly constructed function in the same algebra \(\widetilde{\mathcal{E}}(\mathbb{R}_+,V(\mathbb{R}))\) such that \(\mathfrak{b}=1/\mathfrak{a}\) on the ``boundary" of \(\mathbb{R}_+\times\mathbb{R}\). This result complements the known Fredholm criterion from [K09] for Mellin PDO's with symbols in the closure of \(\widetilde{\mathcal{E}}(\mathbb{R}_+,V(\mathbb{R}))\) and extends the corresponding result by V.S. Rabinovich (see [R98]) on Mellin PDO's with slowly oscillating symbols in \(C^\infty(\mathbb{R}_+\times\mathbb{R})\).

Carpentier, R., H. Liu, M. Silva, and Teresa Sousa. "Rainbow connection for some families of hypergraphs." Discrete Math.. 327 (2014): 40-50. Abstractrc-hypergraphs-preprint.pdf

An edge-coloured path is rainbow if its edges have distinct colours. The rainbow connection number of a connected graph G, denoted by rc(G), is the minimum number of colours required to colour the edges of G so that any two vertices of G are connected by a rainbow path. The function rc(G) was first introduced by Chartrand et al.~[Math.~Bohem., 133(1) (2008), pp.85-98], and has since attracted considerable interest. In this paper, we introduce two extensions of the rainbow connection number to hypergraphs. We study these two extensions of the rainbow connection number in minimally connected hypergraphs, hypergraph cycles and complete multipartite hypergraphs.

Lúcio, Válter, Duarte Faria, António Ramos, and João Ferreira. "Reabilitação Estrutural de Edifícios com Pós-Tensão." ReHabend 2014. Santader 2014. Abstract

n/a

Lúcio, Válter, Hugo Fernandes, and António Ramos. "Reforço de Lajes Fungiformes com Betão Complementar Armado na Face Tracionada." Construção Magazine. 64 (2014).
Young, M. T., S. Hua, L. Steel, D. Foffa, S. L. Brusatte, S. Thüring, O. Mateus, J. Ignacio-Ruiz Omeñaca, Y. Lepage, P. Havilk, and M. B. Andrade. "Revision of the Late Jurassic teleosaurid genus Machimosaurus (Crocodylomorpha, Thalattosuchia)." Royal Society Open Science. 1.140222 (2014): 1-42.young_et_al_2014_machimosaurus_crocodylomorph_revision.pdf
Pinho, Fernando F. S., Válter J. G. Lúcio, and Manuel F. C. BAIÃO. "Rubble Stone Masonry Walls Strengthened by Three-dimensional Steel Ties and Textile Reinforced Mortar Render, under Compression." International Journal of Architectural Heritage: Conservation, Analysis, and Restoration. DOI:10.1080/15583058.2012.727062. 8.5 (2014): 670-689.
Gouveia, Nuno D., Nelson A. G. Fernandes, Duarte M. V. Faria, António M. P. Ramos, and Válter J. G. Lúcio. "SFRC flat slabs punching behaviour - Experimental research." Composites Part B: Engineering. 63 (2014): 161-171. Abstract

The use of randomly distributed steel fibres in the concrete mix improves its mechanical properties. In the particular case of a flat slab-column connection, this solution can provide slabs with an increased load capacity and deformation capacity, allowing a potential reduction of reinforcement. This work presents the experimental study of the behaviour of SFRC flat slabs up to failure under a concentrated loading, accompanied by the study of the mechanical properties of the SFRC, which consisted in three-point loading notched beams, compression and splitting tests. In this study, the hooked end steel fibre dosages varied between 0{%} and 1.25{%} by volume. Test results showed that the inclusion of steel fibres influences both slab stiffness and its load capacity. Increments of load capacity up to 64{%} were obtained in slabs with SFRC compared with the reference slab without fibres. The experimental results were compared with the predictions provided by several existing models. © 2014 Elsevier Ltd. All rights reserved.

Silva, João André, Tiago Vale, Ricardo Dias, Hervé Paulino, and João M. Lourenço Supporting Partial Data Replication in Distributed Transactional Memory. Joint Euro-TM/MEDIAN Workshop on Dependable Multicore and Transactional Memory Systems (DMTM). Vienna, Austria: Euro-TM, 2014. Abstract

Transactional memory (TM) is consistently making its way into mainstream programming, being already deployed by some of the major CPU manufacturers and in several reference compilers. To cope with requirements such as scalability and dependability, recent proposals explore the combination of TM with data replication, bringing TM to distributed environments - conceiving distributed transactional memory (DTM). However, current DTM frameworks support only full data replication. They provide the best possible level of tolerance to data loss, but limit the system's total storage capacity to the capacity of the node with fewer resources, and require coordination among all the system's nodes, an approach bound to hamper scalability in large scale systems. In this context, a partial data replication strategy can help to lessen these shortcomings. Each node replicates only a subset of the system's dataset, an approach that aims at combining the best of data distribution and full replication, while trying to attenuate their disadvantages. The key idea is to allow the dataset to be distributed among the participating nodes and to decrease the number of nodes that have to participate in a transaction's confirmation, as any given transaction only has to be confirmed by the nodes that replicate the data items in its read and write sets. By distributing the data and reducing the coordination cost among nodes, partial data replication leverages the system's scalability. Although this strategy has already been explored by the distributed databases research field, it is yet to be addressed in the context of (D)TM. More specifically, partial data replication has been broadly applied in key-value stores, and even though these work on in-memory data and support transactions, they present significant differences when compared with DTM systems for general purpose programming languages. To this extent, we propose PARdstm, to the best of our knowledge, the first DTM framework to include support for partial data replication. As such, the contributions of this work are: a reasoning on how partial data replication shall be supported in general purpose programming languages (Java, in particular), and a modular software framework that embeds such principles to provide a highly expressive and non-intrusive programming API. Initial experimental results give evidence that our approach may enhance scalability in large scale systems, when compared to full data replication. An ongoing comprehensive study will allow us to assess in which contexts of use (workloads, number of nodes, etc.) partial data replication may be an effective alternative.

Liu, H., Â. Mestre, and Teresa Sousa. "Total rainbow k-connection in graphs." Discrete Applied Mathematics. 174 (2014): 92-101. Abstracttrc-preprint.pdf

Let k be a positive integer and G be a k-connected graph. In 2009, Chartrand, Johns, McKeon, and Zhang introduced the rainbow k-connection number rc_k(G) of G. An edge-coloured path is rainbow if its edges have distinct colours. Then, rc_k(G) is the minimum number of colours required to colour the edges of G so that any two vertices of G are connected by k internally vertex-disjoint rainbow paths. The function rc_k(G) has since been studied by numerous researchers. An analogue of the function rc_k(G) involving vertex colourings, the rainbow vertex k-connection number rvc_k(G), was subsequently introduced. In this paper, we introduce a version which involves total colourings. A total-coloured path is total-rainbow if its edges and internal vertices have distinct colours. The total rainbow k-connection number of G, denoted by trc_k(G), is the minimum number of colours required to colour the edges and vertices of $G$, so that any two vertices of $G$ are connected by $k$ internally vertex-disjoint total-rainbow paths. We study the function trc_k(G) when G is a cycle, a wheel, and a complete multipartite graph. We also compare the functions rc_k(G), rvc_k(G), and trc_k(G), by considering how close and how far apart trc_k(G) can be from rc_k(G) and rvc_k(G).