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2013
dos Santos, Amarante F. P., and C. Cismasiu. "Bridge Hinge-Restrainers Built up of NITI Superelastic Shape-Memory Alloys." New Trends in Smart Technologies . Eds. Christian Boller, and Hartmut Janocha. Saarbrücken: Fraunhofer Verlag, 2013. 195-203.
Santos, Amarante Dos F. P., and Corneliu Cismasiu. "Bridge Hinge-Restrainers Built up of NITI Superelastic Shape-Memory Alloys." New Trends in Smart Technologies . Eds. Christian Boller, and Hartmut Janocha. Saarbrücken: Universität des Saarlandes, Fraunhofer IZFP, 2013. 195-203.urnnbnde0011-n-2564581.pdf
Barbosa, Rui, Diogo Dias, Nuno Lapa, Helena Lopes, and Benilde Mendes. "Chemical and ecotoxicological properties of size fractionated biomass ashes." Fuel Processing Technology. 109 (2013): 124-132. AbstractWebsite

The main aim of this work was to study the chemical and ecotoxicological properties of ashes produced in a biomass boiler of a pulp and paper industry and evaluate possible differences depending on the particle size of bottom and fly ashes. This industry produces electricity by burning eucalyptus and pine bark in a bubbling fluidized bed combustor. Bottom and fly ashes and their size fractions, obtained by sieving, were analysed for a set of metals and leaching behaviour. The eluates were also submitted to ecotoxicological characterization, using five indicators. The highest concentrations of metals and metalloids were found in the lower particle size fractions of bottom and fly ashes. However, generally, it could not be observed any specific releasing pattern of metals depending on the particle size, except for fly ashes in which the releasing rate of some earth and alkali-earth metals seemed to increase for lower particle size fractions. No specific pattern of the ecotoxicity levels could be associated to the different particle size fractions of ashes. The fractions of bottom ashes with 4,000–10,000 μm and > 10,000 μm have presented the lowest ecotoxicity levels. All the samples were classified as ecotoxic, except the fraction of bottom ashes > 10,000 μm.

de Batista, Tiago Afonso Brito Construção e Caracterização de fugas de referência de gases frigorigéneos. Eds. Orlando M. N. D. Teodoro. Faculdade de Ciências e Tecnologia da Universidade Nova de Lisboa. CAPARICA: FCT/UNL, 2013.8_2013_tiago_bat.pdf
Bras, Ana, Rita Gião, Válter Lúcio, and Carlos Chastre. "Development of an injectable grout for concrete repair and strengthening." Cement and Concrete Composites (2013). AbstractWebsite

This paper deals with the coupled effect of temperature and silica fume addition on rheological, mechanical behaviour and porosity of grouts based on CEMI 42.5R, proportioned with a polycarboxylate-based high range water reducer. Preliminary tests were conducted to focus on the grout best able to fill a fibrous network since the goal of this study was to develop an optimized grout able to be injected in a mat of steel fibers for concrete strengthening. The grout composition was developed based on criteria for fresh state and hardened state properties. For a CEMI 42.5R based grout different high range water reducer dosages (0, 0.2%, 0.4%, 0.5%, 0.7%) and silica fume (SF) dosages (0, 2%, 4%) were tested (as replacement of cement by mass). Rheological measurements were used to investigate the effect of polycarboxylates (PCE) and SF dosage on grout properties, particularly its workability loss, as the mix was to be injected in a matrix of steel fibers for concrete jacketing. The workability behaviour was characterized by the rheological parameters yield stress and plastic viscosity (for different grout temperatures and resting times), as well as the procedures of mini slump cone and funnel flow time. Then, further development focused only on the best grout compositions. The cement substitution by 2% of SF exhibited the best overall behaviour and was considered as the most promising compared to the others compositions tested. Concerning the fresh state analysis, a significant workability loss was detected if grout temperature increased above 35°C. Below this temperature the grout presented a self-levelling behaviour and a life time equal to 45 minutes. In the hardened state, silica fumes increased not only the grout’s porosity but also the grout’s compressive strength at later ages, since the pozzolanic contribution to the compressive strength does not occur until 28 days and beyond.

Potewar, T. M., K. T. Petrova, and M. T. Barros. "Efficient microwave assisted synthesis of novel 1,2,3-triazole-sucrose derivatives by cycloaddition reaction of sucrose azides and terminal alkynes." Carbohydr. Res. 379 (2013): 60-67. DOI: 10.1016/j.carres.2013.06.017.
Silva, Manuel A. G., Hugo Biscaia, and Carlos Chastre. "Influence of Temperature Cycles on Bond between GFRP and Concrete." ACI Structural Journal. 110.6 (2013): 977-988. AbstractWebsite

Reinforced concrete (RC) beams externally strengthened with glass fiber-reinforced polymer (GFRP) strips bonded to the soffit may see their load-carrying capacity reduced due to environmental conditions—especially due to the deterioration of bond between the adhesively bonded laminates and concrete, causing premature failure.
More research has been published on the detachment of the laminate progressing from the anchorage zone than on failure induced by the formation of flexural or shear-flexural cracks in the midspan followed by fiber-reinforced polymer (FRP) separation and failure designated as intermediate crack (IC) debonding. An experimental program to study degradation of the GFRP laminate beam specimens after accelerated temperature cycles, namely: 1) freezing-and-thawing type; and 2) cycles of the same amplitude (40°C [104°F]) and an upper limit approximately 70% of the glass vitreous transition temperature of the resin, Tg, is described.
Effects on the bond stress and ultimate capacity are reported. Substantial differences between shear and bending-induced failure and a decrease of bond stresses and engagement of the laminates on the structural response are analyzed.

Bundaleski, N., J. Trigueiro, A. G. Silva, A. M. C. Moutinho, and O. M. N. D. Teodoro. "Influence of the patch field on work function measurements based on the secondary electron emission." JOURNAL OF APPLIED PHYSICS. 113.183720 (2013): 1-11.2013_influence_of_the_patch_field_on_work_function_measurements_based_on_the_secondary_electron_emission.pdf
Bundaleski, Nenad, Stefano Caporali, Sergey P. Chenakin, Augusto M. C. Moutinho, Orlando M. N. D. Teodoro, and Alexander Tolstogouzov. "Ion-induced fragmentation of imidazolium ionic liquids : TOF-SIMS study." International Journal of Mass Spectrometry. 353 (2013): 19-25.2013_ion-induced_fragmentation_of_imidazolium_ionic_liquids.pdf
Biscaia, Hugo C., Carlos Chastre, and Manuel A. G. Silva. "Linear and nonlinear analysis of bond-slip models for interfaces between FRP composites and concrete." Composites Part B: Engineering. 45 (2013): 1554-1568. AbstractWebsite

The paper analyses different analytical and numerical solutions for the debonding process of the FRP-to-concrete interface on shear tests with the FRP plate submitted to a tensile load in one of its ends. From the point of view of the state of the art, two different ways of finding the bond-slip curve from experiments are discussed and analysed. Essentially, three different linear bond-slip models, one exponential model and another power based function are employed in the numerical process. The results are analysed and compared. The differences found in the stress field along the interface, maximum load, maximum slip, ultimate slip, fracture energy and effective bond length are reported. The load-slip behaviour is also presented for the linear and non-linear models herein studied and the influence of the local bond-slip model on the debonding process is discussed. The numerical integration process used on the present study proved to be coherent with the analytical expressions determined for the linear bond-slip models and allowed to verify that maximum load transmittable to the FRP plate is influenced by the square root of the FRP stiffness and fracture energy even when nonlinear bond-slip models are assumed.

Biscaia, Hugo C., Carlos Chastre, and Manuel A. G. Silva. "Nonlinear numerical analysis of the debonding failure process of FRP-to-concrete interfaces." Composites Part B: Engineering. 50 (2013): 210-223. AbstractWebsite

The paper analyses numerical solutions for the process leading to debonding failure of fiber reinforced polymers (FRP)-to-concrete interfaces in shear tests with the FRP plate subjected to a tensile load at one end. Any realistic local nonlinear bond-slip law can be used in the numerical analysis proposed in the present study. However, only a Popovics’ type expression is employed in the numerical process due to its use in different studies found in the literature. Effective bond length (Leff) is discussed and an expression depending on the Popovics’ constant (nP) is proposed to calculate it. Assuming a fracture in pure Mode II, the debonding process is analyzed in detail and distributions of bond stresses and strains in the FRP plate along the interface are presented. The load-displacement behaviour is also presented and the influence of the local bond-slip law on the debonding process is discussed.

Mannion, Philip D., Paul Upchurch, Rosie N. Barnes, and Octávio Mateus. "Osteology of the Late Jurassic Portuguese sauropod dinosaur Lusotitan atalaiensis (Macronaria) and the evolutionary history of basal titanosauriforms." Zoological Journal of the Linnean Society. 168 (2013): 98-206. Abstractmannion_et_al_2013_sauropod_lusotitan_portugal.pdfWebsite

Titanosauriforms represent a diverse and globally distributed clade of neosauropod dinosaurs, but their inter-relationships remain poorly understood. Here we redescribe Lusotitan atalaiensis from the Late Jurassic Lourinhã Formation of Portugal, a taxon previously referred to Brachiosaurus. The lectotype includes cervical, dorsal, and caudal vertebrae, and elements from the forelimb, hindlimb, and pelvic girdle. Lusotitan is a valid taxon and can be diagnosed by six autapomorphies, including the presence of elongate postzygapophyses that project well beyond the posterior margin of the neural arch in anterior-to-middle caudal vertebrae. A new phylogenetic analysis, focused on elucidating the evolutionary relationships of basal titanosauriforms, is presented, comprising 63 taxa scored for 279 characters. Many of these characters are heavily revised or novel to our study, and a number of ingroup taxa have never previously been incorporated into a phylogenetic analysis. We treated quantitative characters as discrete and continuous data in two parallel analyses, and explored the effect of implied weighting. Although we recovered monophyletic brachiosaurid and somphospondylan sister clades within Titanosauriformes, their compositions were affected by alternative treatments of quantitative data and, especially, by the weighting of such data. This suggests that the treatment of quantitative data is important and the wrong decisions might lead to incorrect tree topologies. In particular, the diversity of Titanosauria was greatly increased by the use of implied weights. Our results support the generic separation of the contemporaneous taxa Brachiosaurus, Giraffatitan, and Lusotitan, with the latter recovered as either a brachiosaurid or the sister taxon to Titanosauriformes. Although Janenschia was recovered as a basal macronarian, outside Titanosauria, the sympatric Australodocus provides body fossil evidence for the pre-Cretaceous origin of titanosaurs. We recovered evidence for a sauropod with close affinities to the Chinese taxon Mamenchisaurus in the Late Jurassic Tendaguru beds of Africa, and present new information demonstrating the wider distribution of caudal pneumaticity within Titanosauria. The earliest known titanosauriform body fossils are from the late Oxfordian (Late Jurassic), although trackway evidence indicates a Middle Jurassic origin. Diversity increased throughout the Late Jurassic, and titanosauriforms did not undergo a severe extinction across the Jurassic/Cretaceous boundary, in contrast to diplodocids and non-neosauropods. Titanosauriform diversity increased in the Barremian and Aptian–Albian as a result of radiations of derived somphospondylans and lithostrotians, respectively, but there was a severe drop (up to 40%) in species numbers at, or near, the Albian/Cenomanian boundary, representing a faunal turnover whereby basal titanosauriforms were replaced by derived titanosaurs, although this transition occurred in a spatiotemporally staggered fashion.

Baltazar, LG, F. M. A. Henriques, F. Jorne, and M. T. Cidade. "Performance improvement of hydraulic lime based grouts for masonry consolidation: An experimental study." Structural Studies, Repairs and Maintenance of Heritage Architecture XIII, WIT Transactions on the Built Environment. Southampton: WIT Press, 2013. 417-430.
Ramos, Tania Rodrigues Pereira, Maria Isabel Gomes, and Ana Paula Barbosa-póvoa. "Planning Waste Cooking Oil Collection Systems." Waste Management. 33.8 (2013): 1691-1703. AbstractWebsite

This research has been motivated by a real-life problem of a waste cooking oil collection system characterized by the existence of multiple depots with an outsourced vehicle fleet, where the collection routes have to be plan. The routing problem addressed allows open routes between depots, i.e., all routes start at one depot but can end at the same or at a different one, depending on what minimizes the objective function considered. Such problem is referred as a Multi-Depot Vehicle Routing Problem with Mixed Closed and Open Inter-Depot Routes and is, in this paper, modeled through a Mixed Integer Linear Programming (MILP) formulation where capacity and duration constraints are taken into account. The model developed is applied to the real case study providing, as final results, the vehicle routes planning where a decrease of 13% on mileage and 11% on fleet hiring cost are achieved, when comparing with the current company solution.

Belo, Orlando, Jácome Cunha, João Paulo Fernandes, Jorge Mendes, Rui Pereira, and João Saraiva. "QuerySheet: A Bidirectional Query Environment for Model-Driven Spreadsheets." Proceedings of the 2013 IEEE Symposium on Visual Languages and Human-Centric Computing. VLHCC '13. Washington, DC, USA: IEEE Computer Society, 2013. 199-200. Abstractvlhcc2013-td.pdf

This paper presents a tool, named QUERYSHEET, to query spreadsheets. We defined a language to write the queries, which resembles SQL, the language to query databases. This allows to write queries which are more related to the spreadsheet content than with current approaches.

Pava, J. A., C. Banquet, J. D. Silva, and F. Oliveira. "The Regularized Boussinesq equation: Instability of periodic traveling waves." Journal of Differential Equations. 254.9 (2013): 3994-4023.Website
Sousa, Ana M. M., João Borges, Fernando Silva, Ana M. Ramos, Eurico J. Cabrita, and Maria Pilar Gonçalves. "Shaping the molecular assemblies of native and alkali- modified agars in dilute and concentrated aqueous media via microwave-assisted extraction." Soft Matter. 9 (2013): 3131-3139. AbstractWebsite

The use of agar-based biomaterials for the development of emerging areas, such as tissue engineering or ‘smart materials’ production has recently gained great interest. Understanding how these gel-forming polysaccharides self-organise in aqueous media and how these associations can be tuned to meet the specific needs of each application is thus of great relevance. As an extension of previous pioneering research concerning the application of the microwave-assisted extraction (MAE) technique in the recovery of native (NA) and alkali-modified (AA) agars, this article focuses on the different molecular assemblies assumed by these novel NA and AA when using different MAE routes. The molecular architectures in dilute (5, 10, 50 and 100 mg mL1) and concentrated (1.5% (w/w)) aqueous media were imaged by AFM and cryoSEM, respectively. Relevant structural and physicochemical properties were investigated to support the microscopic data. Different extraction routes led to polysaccharides with unique properties, which in turn resulted in different molecular assemblies. Even at 5 mg mL1, AFM images included individual fibers, cyclic segments, aggregates and local networks. At higher polymer concentrations, the structures further aggregated forming multilayer polymeric networks for AA. The more compact and denser 3D networks of AA, imaged by cryoSEM, and their higher resistance to large deformations matched the 2D-shapes observed by AFM. Depending on the nature of the AA chains, homogeneous or heterogeneous growth of assemblies was seen during network formation. The obtained results support well the view of double helix formation followed by intensive double helix association proposed for agar gelation.

Baptista, Susana, Maria Isabel Gomes, and Ana Paula Barbosa-póvoa. "A stochastic model for a multi-period multi-product closed loop supply chain." XVI Congresso da Associação Portuguesa de Investigação Operacional IO 2013. Bragança, Portugal 2013. 27-37. Abstract2013_baptistagomesbpovoa_io2013.pdf

In this work we propose a stochastic model for the design and planning of closed-loop supply chains.
Uncertainties in demand and return volumes are modelled together with uncertain transportation
costs. A two-stage stochastic programming is developed and a sensitivity analysis to the worst-case
probability is performed in order to test the solution robustness. Finally, in order to prove the
goodness of the stochastic approach, the value of the stochastic solution and the value of perfect
information are computed. An example based on a real case shows the model applicability.

Morgado, Carmen, and Fernanda Barbosa. "A Structured Approach to Problem Solving in CS1/2." International Journal of Advanced Computer Science. Vol. 3.(7) (2013): ISSN: 2251-6379.
Amado, Miguel P., and L. Barroso. "SUSTAINABLE CONSTRUCTION: WATER USE IN RESIDENTIAL BUILDINGS IN PORTUGAL." International Journal of Sustainable Construction Engineering and Technology ISSN: 2180-3242. 4.2 (2013): 14-22.
Ferrão, Lúcio Emanuel Represas, Seco João Ricardo Viegas Da Costa, Caires Luis Manuel Marques Da Costa, Caleira Borrêga, Gonçalo Filipe Xavier, António Augusto Vieira Melo, and OutSystems-Software em Rede SA SYSTEMS, METHODS, AND APPARATUS FOR MODEL-BASED SECURITY CONTROL., 2013. Abstract

n/a

Ramos, Tânia, Maria Isabel Gomes, and Ana Paula Barbosa-póvoa. "Tactical and Operational Planning in Reverse Logistics Systems with Multiple Depots." XVI Congresso da Associação Portuguesa de Investigação Operacional IO 2013. Bragança, Portugal 2013. 286-295.2013_ramosgomesbpovoa_io2013.pdf
Brusatte, S. L., R. J. Butler, O. Mateus, J. S. Steyer, and J. H. Whiteside Terrestrial vertebrates from the Late Triassic of Portugal: new records of temnospondyls and archosauriforms from a Pangaean rift sequence. 61st Symposium on Vertebrate Palaeontology and Comparative Anatomy. Edinburgh, 2013. Abstractbrusatte_et_al_2013_triassic_algarve_portugal_temnospondyls_svpca.org_years_2013_edinburgh_abstracts.pdf

The Late Triassic (ca. 237-201.5 million years ago) was a transitional interval in the evolution of terrestrial ecosystems, during which ‘modern’ clades such as archosaurs and mammals were radiating while ‘archaic’ groups such as temnospondyl amphibians and basal synapsids remained abundant. Little is known about the Triassic terrestrial (nonmarine) vertebrates of the Iberian Peninsula. The Algarve Basin of southern Portugal is an extensional rift basin formed during the breakup of Pangaea, which is filled with terrestrial, lacustrine, and marginal marine siliciclastics of the Grés de Silves Formation, interbedded with CAMP basalts that mark the end-Triassic extinction (radioisotopically dated to ~198-201.5 Ma). Since 2009, our field project in the Algarve has discovered numerous vertebrate specimens within the Grés de Silves, including a monodominant bonebed containing hundreds of specimens of metoposaurids, a peculiar group of temnospondyls that filled crocodile-like predatory niches in lacustrine and fluvial environments. These specimens appear to belong to a new species of Metoposaurus, similar to M. diagnosticus and M. krasiejowensis from central Europe but possessing several putative autapomorphies of the braincase and lower jaw. We also discovered a mandible of a phytosaur, the first specimen of these long-snouted, semi-aquatic archosauriforms from the Iberian Peninsula. These discoveries of characteristic Carnian Norian taxa indicate that the fossil-bearing portion of the Grés de Silves is Late Triassic in age, and provide further evidence that metoposaurids and phytosaurs commonly occurred together in low palaeolatitudes during this time.

Mota, Bruna, Maria Isabel Gomes, and Ana Paula Barbosa-póvoa. "Towards supply chain sustainability: balancing costs with environmental and social impacts." Computer Aided Process Engineering. Eds. Andrzej Kraslawski, and Ilkka Turunen. Elsevier, 2013. 895-900. Abstract2013_motagomesbpovoa_escape23.pdf

This work presents a multi-objective optimization methodology that accounts for economic, environmental and social concerns in a supply chain with reverse flows. Environmental impact assessment is considered through the use of Recipe 2008. A social benefit indicator is developed where the creation of employment in less developed regions is preferred. The multi-objective approach is used to reach a solution of compromise between the three sustainability pillars. The model is applied to a case study developed in collaboration with a Portuguese company, leader in battery production.

Brazinha, Carla, Ana P. Fonseca, Helena Pereira, and Orlando M. N. D. Teodoro. "{Gas transport through cork: Modelling gas permeation based on the morphology of a natural polymer material}." Journal of membrane science. 428 (2013): 52-62. Abstract2013_gas_transport_through_cork-_modelling.pdf

Natural polymers have been studied during the last years for the transport and separation of liquid and gas mixtures, in terms of solubility and permeability data, and their structure and mechanical properties have been characterised. However, no transport models have been reported, relating transport with the material morphology. Cork is a natural cellular material containing three structural polymers (suberin, lignin and polysaccharides). Cork is considered a natural polymer, with economic relevance due to its sealing, non-toxic, stable and low-density properties. Corkwas characterised in this work in terms of its solubility and permeability data in relation to various gases with different molecular mass: He, O2,N2,CO2 and 1,1,1,2-tetrafluoroethane (R134a). A morphological analysis of the structure of the cork sample chosen in this work was also performed using SEM (scanning electron microscopy) and TEM (transmission electron microscope) image analysis, which took into account the variation of each relevant structural parameter. A transport model was developed supported on the morphology of cork characterised in this work. The transport model developed considers that gas permeation occurs through the plasmodesmata, which are channels with approximately 100 nm of diameter that cross the cell walls of the cork cells. It was found that gas transport follows a Knudsen mechanism, as proved by the gas permeability behaviour with increasing gasmolecularmass, with a negligible contribution of viscous transport to the total flux. &