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2014
Gralha, Catarina, Miguel Goulão, and João Araújo. "Identifying modularity improvement opportunities in goal-oriented requirements models." 26th International Conference on Advanced Information Systems Engineering, CAiSE 2014. Thessaloniki, Greece 2014. Abstract

Goal-oriented Requirements Engineering approaches have become popular in the Requirements Engineering community as they provide expressive model elements for requirements elicitation and analysis. However, as a common challenge, they are still struggling when it comes to managing the accidental complexity of their models. In this paper, we provide a set of metrics, which are formally specified and have tool support, to measure and analyze the complexity of goal models, in particular i* models. The aim is to identify refactoring opportunities to improve the modularity of those models, and consequently reduce their complexity. We evaluate these metrics by applying them to a set of well-known case studies from industry and academia. Our results allow the identification of refactoring opportunities in the evaluated models.

Chastre, C., M. Ludovico-Marques, J. Saumell, M. Guerrero, and M. Delgado. "Surveying of Sandstone Monuments: New and Traditional Methodologies to Assess Viability of Conservation Actions." 40th IAHS Word Congress of Housing. Sustainable Housing Construction. Funchal, Portugal 2014. ID 307 (10p). Abstract40_iahs_chastre_-_ext.abstract.pdf

Sandstone building stones are important in the building elements of Portuguese monuments, particularly in the western and southern regions. Alveolization due to salt crystallization was the most important degradation pattern found in the old sandstone façades of St. Leonardo’s Church, a Portuguese monument built in Atouguia da Baleia village in the Middle Age. Its sandstone façades have a widespread distribution of deep and large alveolization patterns mainly on portals and vaults that appeared as a result of the past and present vicinity of seashore. In this paper a summary of conservation interventions carried out in the past century in St. Leonardo’s Church is presented, as well as a summary of the studies carried out in the last decade. Then the degradation patterns on the sandstone walls of St. Leonard’s Church are shown and finally the evolution of the alveolization occurred on the sandstone walls over the last sixty to seventy years is analysed. Visual inspection of sandstone walls is compared with a survey performed by laser scanning, which seems to be a powerful technology to carry out 3D geometric modelling of the building elements of stone monuments and also the 3D mapping of stone degradation patterns.

Ludovico-Marques, M., and C. Chastre. "Conservation of sandstone monuments: a new approach in consolidation treatments." 40th IAHS Word Congress of Housing. Sustainable Housing Construction. Funchal, Portugal 2014. ID 211 (10p). Abstract40_iahs_ludovico-marques_-_ext.abstract.pdf

Sandstones are very important in the building elements of world’s historical and cultural heritage. The façades of St. Leonard’s church in Atouguia da Baleia village in western region of Portugal are an outstanding example of the effect of alveolization on going for several centuries. In Middle ages there was an harbour and a sodium chloride rich environment near this church was responsible for this significant stone degradation pattern.
A new approach of consolidating products application on stone walls façades based on Karsten pipe using total head to allow full absorption of stone was followed.
Experimental research, based on physical and mechanical tests, was carried out on selected representative samples of a variety of sandstones on monuments treated with ethyl silicates in order to assess the effectiveness and harmfulness of these treatments.
The comparison of results between traditional immersion applications and Karsten pipe’s based procedure on stone monument indicate the potential viability of this new approach when difficult conditions of consolidating products’ absorption occurs on stone monuments.

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.
Alcafache, A. O., and M. P. Amado. "Sustainable construction: Water efficiency in housing sector." 40th IAHS World Congress in Housing – Sustainable Housing Construction. 235 - ISBN: 978-989-98949-0-7. Funchal, Madeira - PT: IteCons - Universidade de Coimbra, 2014.
Schedel, J., and M. P. Amado. "Urban Regeneration: More Energy, Less Carbon." 40th IAHS World Congress in Housing – Sustainable Housing Construction. 49, ISBN: 978-989-98949-0-7. Funchal, Madeira - PT: IteCons - Universidade de Coimbra, 2014.
Neves, S. O., P. Rodrigues, and M. P. Amado. "Contribution of the social sciences in the transformation of informal communities." 40th IAHS World Congress in Housing – Sustainable Housing Construction. 21 - ISBN: 978-989-98949-0-7. Funchal, Madeira - PT: IteCons - Universidade de Coimbra, 2014.
Ramalhete, I., M. P. Amado, and H. Farias. "Low Cost Adaptive Housing Model." 40th IAHS World Congress in Housing – Sustainable Housing Construction.54, ISBN: 978-989-98949-0-7. Funchal, Madeira - PT: IteCons - Universidade de Coimbra, 2014.
Neves, S. O., and M. P. Amado. "Incremental Housing as a method to the Sustainable Habitat ." 30th International PLEA . Vol. II - 1-8. Bangalore, India: Centre for Advanced Research in Building Science and Energy (CARBSE), CEPT University, 2014.
Pinho, F. F. S. "Colapso de pavimento elevado num edifício habitado. Causas e medidas de segurança imediatas." CNME2014 - 9º Congresso Nacional de Mecânica Experimental. Universidade de Aveiro 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.
Ludovico-Marques, Marco, and Carlos Chastre. "Effect of consolidation treatments on mechanical behaviour of sandstone." Construction and Building Materials. 70 (2014): 473-482. AbstractWebsite

Experimental research was carried out about into ethyl silicate applications on sandstone samples. Consolidation was assessed by drilling strength, impregnation depth and also monotonic and cyclic uniaxial compressive tests in order to evaluate the compressive mechanical behaviour of treated sandstone. The stress–strain compression diagrams showed a significant increase in the values of mechanical parameters after consolidation treatments. The difference in compressive strength values between monotonic and cyclic compression disappears after the consolidation treatments. An equation of consolidation effect was obtained from an analytical model by means of compressive behaviour assessed by stress–strain diagrams. These sandstone samples have values of porosity similar to the more weathered variety of sandstone found in facades of monuments in the village of Atouguia da Baleia, in the western region of Portugal. The most important degradation pattern found on sandstone building stones is alveolization caused by salt crystallization since the Middle Ages.

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.

Sabino, André, Armanda Rodrigues, Miguel Goulão, and João Gouveia. "Indirect Keyword Recommendation." International Conference on Intelligent Agent Technology, WIC 2014. Warsaw, Poland: IEEE/WIC/ACM, 2014. Abstractsabino2014wic.pdf

Helping users to find useful contacts or potentially interesting subjects is a challenge for social and productive
networks. The evidence of the content produced by users must be considered in this task, which may be simplified by the use of the meta-data associated with the content, i.e., the categorization supported by the network – descriptive keywords, or tags. In this paper we present a model that enables keyword discovery
methods through the interpretation of the network as a graph, solely relying on keywords that categorize or describe productive items. The model and keyword discovery methods presented in this paper avoid content analysis, and move towards a generic approach to the identification of relevant interests and, eventually,
contacts. The evaluation of the model and methods is executed by two experiments that perform frequency and classification analyses over the Flickr network. The results show that we can efficiently recommend keywords to users.

Pinho, Fernando F. S., Manuel F. C. BAIÃO, and Válter J. G. Lúcio. "Reabilitação estrutural de paredes de alvenaria de pedra. Avaliação experimental." REHABEND 2014: Congresso Latinoamericano - Patología de la Construcción, Tecnología de la Rehabilitación y Gestión del Patrimonio. Santander, Espanha 2014.
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

Mateus, Octávio. "Degradation processes and consolidation of Late Jurassic sandstone dinosaur tracks in museum environment (Museum of Lourinhã, Portugal)." Geophysical Research Abstracts. Vol. Geophysical Research Abstracts. 2014. EGU2014-9026–1, 2014. Abstract
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Mateus, Octávio. "Elephas and other vertebrate fossils near Taghrout, Morocco." Journal of Vertebrate Paleontology. Vol. Program and Abstracts, 2014. 2014. 178. Abstract
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Mateus, Octávio. "Geological and paleoecological setting of a marine vertebrate bonebed from the Lower Maastrichtian at Bentiaba, Angola." Proceedings of the Secondary Adaptation of Tetrapods to Aquatic Life. 2014. NA. Abstract

A single, geographically and temporally restricted horizon at Bentiaba, Angola (14.3° S), preserves a concentration of skeletons and isolated elements representing sharks, rays, bony fish, at least three species of turtles, two species of plesiosaurs, at least five species of mosasaurs, and rare volant and terrestrial forms. The concentration, referred to as the Bench 19 Fauna, formed on a narrow continental shelf at paleolatitude 24°S as predicted by paleomagnetic data and confirmed by plate motion models. The shelf evolved as a transform passive margin along faults associated with the opening of the South Atlantic. Latitude 24°S falls today along the coast of northern Namibia, an area of intense upwelling and hyperarid coastal desert. The Namibe Basin in southern Angola is separated from the Walvis Basin of Namibia by the Walvis Ridge, and the continental shelf in northern Namibia is eight times the width of that at Bentiaba. However, the sediment entombing the fossils at Bentiaba is an immature feldspathic sand, shown by detrital zircon ages to be derived from nearby exposed granitic shield rocks, suggesting similar climatic and drainage conditions between the two regions. Temporal control of the Bentiaba section is provided by magnetostratigraphy and stable carbon isotope chemostratigraphy anchored by an Ar40/Ar39radiometric date on basalt. The age of Bench 19 is constrained to chron C32n.1n and thus falls between 71.4 and 71.64 Ma. Massive bedding without hummocky cross-bedding or other sedimentary structures indicates deposition in shallow water below wave base. δ18O analysis of bivalve shells indicates a water temperature of 18° C immediately below Bench 19. Nearest neighbor distance peaks at 5 m (n=19

Valtchev, {Stanimir Stoyanov}, and DEE Group Author. "Perspectives of Tunnel FET (TFET) in Ultra-Low- Power Analog-Circuit design." Proceedings of the XVIII Conference on the Design of Circuits and Integrated Systems Donostia - San Sebastián, Nov. 2013. 2014. 152-157. Abstract

The improved characteristics of Tunnel FETs (TFETs) like steep sub-threshold swing and low off-currents make them an attractive choice for low power operations compared to MOSFETs and Multi-gate FETs like FINFETs. Such characteristics are favorable to digital design, but the drain current saturation in their output characteristics can also benefit the analog design. In this paper, it is shown by simulations that analog characteristics as voltage gain, power consumption and bandwidth are improved using TFETs compared to their counterparts, at a sub-22 nm technology node and 0.8 V supply voltage.

Hendrickx, Christophe, and Octávio Mateus. "Torvosaurus gurneyi n. sp., the largest terrestrial predator from Europe, and a proposed terminology of the maxilla anatomy in nonavian theropods." PLoS ONE. 9 (2014): e88905. Abstracthendrickx_mateus_2014_torvosaurus_portugal.pdfWebsite

The Lourinhã Formation (Kimmeridgian-Tithonian) of Central West Portugal is well known for its diversified dinosaur fauna similar to that of the Morrison Formation of North America; both areas share dinosaur taxa including the top predator Torvosaurus, reported in Portugal. The material assigned to the Portuguese T. tanneri, consisting of a right maxilla and an incomplete caudal centrum, was briefly described in the literature and a thorough description of these bones is here given for the first time. A comparison with material referred to Torvosaurus tanneri allows us to highlight some important differences justifying the creation of a distinct Eastern species. Torvosaurus gurneyi n. sp. displays two autapomorphies among Megalosauroidea, a maxilla possessing fewer than eleven teeth and an interdental wall nearly coincidental with the lateral wall of the maxillary body. In addition, it differs from T. tanneri by a reduced number of maxillary teeth, the absence of interdental plates terminating ventrally by broad V-shaped points and falling short relative to the lateral maxillary wall, and the absence of a protuberant ridge on the anterior part of the medial shelf, posterior to the anteromedial process. T. gurneyi is the largest theropod from the Lourinhã Formation of Portugal and the largest land predator discovered in Europe hitherto. This taxon supports the mechanism of vicariance that occurred in the Iberian Meseta during the Late Jurassic when the proto-Atlantic was already well formed. A fragment of maxilla from the Lourinhã Formation referred to Torvosaurus sp. is ascribed to this new species, and several other bones, including a femur, a tibia and embryonic material all from the Kimmeridgian-Tithonian of Portugal, are tentatively assigned to T. gurneyi. A standard terminology and notation of the theropod maxilla is also proposed and a record of the Torvosaurus material from Portugal is given.