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2013
Amado, M. P., F. Poggi, and A. Amado Final Report of the Project Oeiras E-CITY . CAPARICA: GEOTPU FCT UNL, CMO, 2013.
Larrinaga, Pello, Carlos Chastre, José T. San-José, and Leire Garmendia. "Non-linear analytical model of composites based on basalt textile reinforced mortar under uniaxial tension." Composites Part B: Engineering. 55 (2013): 518-527. AbstractWebsite

The recent development of inorganic based composites as low-cost materials in reinforced concrete structural strengthening and precast thin-walled components, requires the creation of models that predict the mechanical behaviour of these materials. Textile Reinforced Mortar (TRM) shows complex stress–strain behaviour in tension derived from the heterogeneity of its constituent materials. This complexity is mainly caused by the formation of several cracks in the inorganic matrix. The multiple cracking leads to a decrease in structural stiffness. Due to the severe conditions of the serviceability limit state in structural elements, the prediction of the stress–strain curve is essential for design and calculation purposes. After checking other models, an empirical nonlinear approach, which is based on the crack control expression included in the Eurocode 2, is proposed in this paper. Following this scope, this paper presents an experimental campaign focused on 31 TRM specimens reinforced with four different reinforcing ratios. The results are analysed and satisfactorily contrasted with the presented non-linear approach.

Boavida, Nuno, Manuel Baumann, António Brandão Moniz, Jens Schippl, Marcel Weil, and Max Reichenbach Technology transition towards e-mobility: technology assessment as a tool for policy design. International Colloquium of GERPISA - The International Network of the Automobile. Paris: GERPISA, 2013.
Amarante dos Santos, Filipe, and Corneliu Cismasiu. "Vibration control in civil engineering using SMAs." Workshop on "Processing, Characterization and Applications of Shape Memory Alloys". Caparica: FCT-UNL, 2013.
Biscaia, Hugo C., Carlos Chastre, and Manuel A. G. Silva. "A smeared crack analysis of reinforced concrete T-beams strengthened with GFRP composites." Engineering Structures. 56 (2013): 1346-1361. AbstractWebsite

The strengthening of reinforced concrete structures with laminates of fibre reinforced polymeric (FRP) matrix has received considerable attention, although there still is lack of information on the more adequate modelling of the interface between FRP composites and concrete. An experimental programme is described and was designed to: (i) characterise glass FRP-to-concrete interface by shear tests; (ii) analyse reinforced concrete T-beams with external GFRP plates. Double shear tests were carried out based on 15 cm cubes with GFRP bonded to two opposite faces. The concrete T-beams were 3.0 m long and 0.28 m high and were loaded till rupture in 4-point bending tests. The external reinforcement system showed great strength increment in relation to the non retrofitted T-beam, confirming to be an effective approach to the flexural strengthening of RC beams. The computational analysis was based on a three dimensional smeared crack model. In total, 22 computational analyses were made. Models with and without interface FE associated with Mohr–Coulomb failure criterion for the FRP-to-concrete interface were defined and different strength types of concrete were considered. The rigid interface does not predict the rupture of the T-beam with precision; however, the results obtained for low concrete strengths revealed that rigid interfaces can be assumed when conjugated with the fixed crack approach. Consequently, a slightly stiffer response of the beam is obtained. The maximum bond stresses obtained from Finite Element Analysis (FEA) revealed that the models with rigid interfaces developed lower bond stresses due to the lack of relative displacements between both materials. The effects of assuming either fixed or rotated crack approaches were also compared. The rotated crack conjugated to a fine mesh in the vicinity of the GFRP-to-concrete stress led to a very good estimation of the bond stresses along the interface. The prediction of the T-beam rupture was also estimated with better results when the rotated crack was used in the model. In general, the FEA predicted with very good results the de-bonding of the GFRP-to-concrete interface of T-beams externally bonded with GFRP composites.

Biscaia, Hugo C., Carlos Chastre, and Manuel A. G. Silva. "Modelling GFRP-to-concrete joints with interface finite elements with rupture based on the Mohr-Coulomb criterion." Construction and Building Materials. 47 (2013): 261-273. AbstractWebsite

The strengthening of reinforced concrete structures by means of externally bonded fibre reinforced polymers (FRPs) is now routinely considered and applied in the retrofit or strengthening of structures. FRP composites have received a considerable attention from civil engineers in recent years due to the high strength-weight and stiffness/weight ratios when compared to other materials. However, when FRP composites are bonded to a concrete surface, there is a persistent potential problem that the FRP plates may debond prematurely from the concrete. This is a very important issue for the engineers who have to focus on the computational modelling of this phenomenon. Some studies can be found in literature on computational modelling. However, there is very little information about the best modelling of the interface between FRP composites and concrete and this work is intended to help bridge this gap. The computational analysis presented here is based on three-dimensional software which assumes the smeared crack model, and the interface finite elements (FEs) used have a rupture criteria based on the Mohr-Coulomb criterion with tension cut-off. The definition of these FEs was based on double shear tests that were performed specifically for this purpose and they have shown that the debonding phenomenon can be predicted with some accuracy. In total, 10 double shear models were studied and the results were compared with the 21 experimental tests performed. The double shear tests consisted of applying loads to 2 layered GFRP laminates bonded to a 150 mm concrete cube with a bonded area of 150 × 80 mm (length × width). Double shear models with and without a gap interface were considered in order to emphasize the importance of modelling the GFRP-to-concrete interface with interface finite elements. The effect of the concrete strength on the interface performance was also considered. An externally bonded reinforcement (EBR) concrete T-beam strengthened with 2 GFRP layers is presented to illustrate the application of the method. The wet lay-up technique was used for the external reinforcement of a reinforced concrete T-beam and then tested under a four point bending test until rupture. The results are reported and differences between the numerical and the experimental results are discussed.

Liu, H., and Teresa Sousa. "Monochromatic K_r-Decompositions of Graphs." Electronic Notes in Discrete Mathematics. 43 (2013): 121-127. Abstractmono-clique-ep100.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 k-edge-colored graph G of order n, 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.

Sampaio, Bruno, Carmen Morgado, and Fernanda Barbosa. "Collaborative Quiz Development with EPIK." Proceedings of International Conference on Education and Learning Tecnologies (EDULEARN). Barcelona, Spain 2013.
Pais, {João José Cardoso}, {José Carlos Ribeiro} Kullberg, {João Miguel Dias Joanaz de} Melo, Octávio Mateus, and {José António de} Almeida Arrábida - al-rábita. Associação de Municípos da Região de Lisboa, 2013. Abstract

The publication of the present work - rightly designated as the book of Arrabida's nomination file for inscription on the World Heritage list - has for all of us a special significance as it represents, in a sense, the culmination of a complex, challenging and rewarding process. As is widely known, the Arrábida is included since 2004 in UNESCO's Portuguese tentative list, with AMRS being one of this process' promoters. It wouldn't be appropriate to describe here all the details, but it is fair to say that since 2004 to the present day, we've come a long way in recovering and valuing the Arrábida. It is with sincere satisfaction that we can say: our knowledge of the Property is now deeper, up to date and much more accurate, doing justice to the exceptional values contained within the Arrábida - which is well expressed in the work now published, based on researches and works of the highest scientific value. This is also a regional development project, to value our lands, people and the natural and cultural heritage. The Setúbal's Peninsula is a region that contains within its territory a vast natural and cultural heritage, being the Arrábida one of the most beautiful and significant natural areas in the Mediterranean. The Arrábida Mountain is a place with its own identity, being the result of a long history of Man's adaptation to Nature. It is a place of unmistakable aesthetic beauty, a unique place where nature and culture intertwine; it is a place of contrasts, of land and sea, sky and mountains, a place of combined actions by Man and Nature. Place of vibrant social practices, of rituals and festivals, of knowledge, of representations and expressions, of instruments, objects and artifacts. Place with a history that must be preserved and bequeathed to future generations. Place with monuments of vanished civilizations, but also of living traditions. These are some of the values supporting the Arrábida's nomination for the World's Heritage list. It is a complex and demanding nomination file, which this work is an illustrative sample of. A mixed application - as it includes both the natural and cultural heritage - which, given the richness and uniqueness of the Property in question, is fully justified. It is our profound conviction that this Nomination streamlines the potential of our region, bringing benefits not only to the local population, but also to the whole country. To that extent, it is also a sign of hope and confidence showing that it is possible to build a different future; that by investing in our people, in their abilities, knowledge and traditions, it is possible to create a sustainable development; that is possible to leave for future generations a legacy of which we are proud of having worked on. To be able enjoy this magnificent edition is a step in that direction.

da} Rocha, {Rogério Eduardo Bordalo, {José Carlos Ribeiro} Kullberg, and Octávio Mateus. "A Bacia Lusitaniana: Estratigrafia, Paleogeografia e Tectónica." Geologia de Portugal no contexto da Ibéria. Eds. Dias, R. Araújo, A, Terrinha, P., and {J. C. } Kullberg. Escolar Editora, 2013. 195-347. Abstract
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Mateus, Octávio Cabinda revisited: age and environment of new Cenozoic vertebrate fossils from northern Angola. Vol. 45., 2013. Abstract

In the early 20thcentury, Belgian naturalists reported Paleocene and Eocene sharks, the bothremydid pleurodiran turtleTaphosphrys(formerlyBantuchelys), and a neosuchian and the dyrosaurid crocodyliformCongosaurusfrom coastal outcrops near Landana in the northern province of Cabinda, Angola. In 1935, rare and fragmentary mammals were reported from strata at Malembo Point, south of Landana, and originally considered to be Miocene in age. Subsequent re-identification of the mammal fossils suggested that the Malembo deposits are Lower Oligocene based on the presence of an arsinoithere and hyracoids. An anthropoid canine, originally identified as a carnivore incisor, was also recognized. In four recent expeditions to Cabinda, Projecto PaleoAngola has traced and measured the stratigraphy between Landana and Malembo Point and sampled these deposits for pollen, stable isotopes, detrital zircons, paleomagnetic stratigraphy, and for U/Pb dating of bones, teeth, and coprolites. Although the faunas from all Cabinda localities are dominated by sharks and rays, new discoveries from Landana include a complete cheloniid cryptodire turtle skull, a small snake vertebra, and a bird bone. Discoveries from the Malembo level include a narrow-snouted crocodyliform similar toCongosaurusandEuthecodon, an arsinoithere anterior tooth, an upper molar similar to that of the ptolemaiidanKelba, an unidentified mammalian incisor, and a large primate-like premolar. Recent biostratigraphic advances in East Africa and the new fossil discoveries in Cabinda suggest similarity to late Oligocene faunas in Ethiopia and Kenya, although the large primate-like premolar is unique. To this day, the fossil localities of Malembo provide the only coastal, low latitude, low elevation record of West African Cenozoic terrestrial mammals. https://gsa.confex.com/gsa/2013AM/webprogram/Paper232115.html

Mateus, Octávio. "Cathetosaurus as a valid sauropod genus and comparisons with Camarasaurus." Journal of Vertebrate Paleontology. 2013. 173. Abstract
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Mateus, Octávio Decapod crustacean body and ichnofossils from the Mesozoic of Portugal. Vol. NA., 2013. Abstract

Book of abstracts of the 5th Symposium on Mesozoic and Decapod Crustaceans

Gonçalves, Ricardo, and José Júlio Alferes. "Decidability and Implementation of Parametrized Logic Programs." Logic Programming and Nonmonotonic Reasoning, 12th International Conference, LPNMR 2013. Springer-Verlag, 2013. 361-373. Abstractlpnmr13a.pdf

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Gonçalves, Ricardo, and José Júlio Alferes. "Deontic logic programs." International conference on Autonomous Agents and Multi-Agent Systems, AAMAS '13. IFAAMAS, 2013. 1333-1334. Abstractaamas13.pdf

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Alferes, José Júlio, Ricardo Gonçalves, and João Leite. "Equivalence of defeasible normative systems." Journal Of Applied Non-Classical Logics. 23 (2013): 25-48. Abstractjancl13.pdf

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Gomes, Ana Sofia, and José Júlio Alferes. "Extending Transaction Logic with External Actions." Theory And Practice Of Logic Programming. 13.4-5-Online-Supplement (2013). Abstracticlp13.pdf

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Gomes, Ana Sofia, and José Júlio Alferes. "External Transaction Logic with Automatic Compensations." Computational Logic in Multi-Agent Systems - 14th International Workshop, CLIMA XIV. Springer-Verlag, 2013. 239-255. Abstractclima13.pdf

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Mateus, Octávio. "First definitive association between embryonic Allosaurus bones and prismatoolithus eggs in the Morrison Formation (Upper Jurassic, Wyoming, USA)." Journal of Vertebrate Paleontology. 2013. 101. Abstract

Despite more than a century of collecting, resulting in one of the best-studied vertebrate fossil records anywhere in the world, the Upper Jurassic Morrison Formation has produced surprisingly few examples of dinosaur eggs associated with embryonic remains. Even more puzzling, none of these seem to pertain to the theropod Allosaurus, one of the most common and best-understood dinosaur taxa in the formation. Here we report on a dinosaur nest site that has produced both abundant prismatoolithid eggshell and embryonic (or perinatal) bones of Allosaurus from Fox Mesa, Wyoming. This represents the first such discovery for any theropod in the Jurassic of North America. The nest is heavily weathered but contains a few ellipsoid eggshell clusters that suggest an egg size of about 8 x 6.5 cm. Study of the eggshell morphology and microstructure confirms that a single egg type is present throughout, which is indistinguishable from Prismatoolithus coloradensis. All of the identifiable embryonic materials pertain to theropods, and two premaxillae specimens show the five alveoli diagnostic for Allosaurus among Morrison theropods. This confirms the theropod origin of Prismatoolithus eggs and implicates Allosaurus as the specific Morrison parent taxon. As a result, it is now possible to assign several previous discoveries of dinosaur eggs and potential nests to Allosaurus, including the isolated egg from the Cleveland-Lloyd Quarry. This discovery also calls into question prior assignments of Prismatoolithus eggs to ornithopods, and suggests that more detailed study of such sites is warranted. Prismatoolithus eggshells are also associated with the Upper Jurassic theropod Lourinhanosaurus from Portugal, along with larger embryos that exhibit four premaxillary alveoli.

Alferes, José Júlio, Matthias Knorr, and Kewen Wang. "Forgetting under the Well-Founded Semantics." Logic Programming and Nonmonotonic Reasoning, 12th International Conference, LPNMR 2013. Springer-Verlag, 2013. 36-41. Abstractforgettinglpnmr13.pdf

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Alferes, José Júlio, Matthias Knorr, and Terrance Swift. "Query-Driven Procedures for Hybrid MKNF Knowledge Bases." ACM Transactions On Computational Logic. 14.2 (2013). Abstracttocl13.pdf

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Alexandre, Fernando, Ricardo Marques, and Hervé Paulino. "Esqueletos Algorítmicos para Paralelismo de Tarefas em Sistemas Multi-GPU." INForum 2013 - Atas do 5º Simpósio de Informática. Eds. João Cachopo, and Beatriz Sousa Santos. Évora, Portugal: Escola de Ciências e Tecnologia da Universidade de Évora, 2013. 238-249. Abstract

A crescente utilização de Unidades de Processamento Gráfico (GPUs) na computação de caráter geral levanta questões de desempenho e de escalabilidade. Para responder a estes requisitos de forma efetiva, cada vez mais se recorre à utilização colaborativa de vários GPUs num só sistema. Esta abordagem introduz, no entanto, novos desafios, tal como a decomposição do domínio do problema e a gestão da possível heterogeneidade dos dispositivos. Neste contexto assume particular relevância a proposta de abstrações que escondam a complexidade da programação destes sistemas. Existe já algum trabalho na área, mas este restringe-se ao paralelismo de dados. Por conseguinte, neste artigo abordamos a utilização de uma biblioteca de esqueletos algorítmicos, Marrow, para a exploração de paralelismo de tarefas em sistemas computacionais com estas características. Os resultados são promissores, apresentado a escalabilidade esperada nos sistemas testados.

Silva, João, Tiago Vale, João M. Lourenço, and Hervé Paulino. "Replicação Parcial com Memória Transacional Distribuída." INForum 2013 - Atas do 5º Simpósio de Informática. Eds. João Cachopo, and Beatriz Sousa Santos. Évora, Portugal: Escola de Ciências e Tecnologia da Universidade de Évora, 2013. 310-321. Abstract

Os sistemas de memória transacional distribuída atuais recorrem essencialmente à distribuição ou à replicação total para distribuir os seus dados pelos múltiplos nós do sistema. No entanto, estas estratégias de replicação de dados apresentam limitações. A distribuição não oferece tolerância a falhas e a replicação total limita a capacidade de armazenamento do sistema. Nesse contexto, a replicação parcial de dados surge como uma solução intermédia, que combina o melhor das duas anteriores com o intuito de mitigar as suas desvantagens. Esta estratégia tem sido explorada no contexto das bases de dados distribuídas, mas tem sido pouco abordada no contexto da memória transacional e, tanto quanto sabemos, nunca antes tinha sido incorporada num sistema de memória transacional distribuída para uma linguagem de propósito geral. Assim, neste artigo propomos e avaliamos uma infraestrutura para replicação parcial de dados para programas Java bytecode, que foi desenvolvida com base num sistema já existente de memória transacional distribuída. A modularidade da infraestrutura que apresentamos permite a implementação de múltiplos algoritmos e, por conseguinte, avaliar em que contextos de utilização (workloads, número de nós, etc.) a replicação parcial se apresenta como uma alternativa viável a outras estratégias de replicação de dados.

Parreira, Daniel, and Hervé Paulino. "Uma Abordagem Alto Nível ao Controlo de Concorrência Componível Centrado nos Dados." INForum 2013 - Atas do 5º Simpósio de Informática. Eds. João Cachopo, and Beatriz Sousa Santos. Évora, Portugal: Escola de Ciências e Tecnologia da Universidade de Évora, 2013. 298-309. Abstract

O controlo da concorrência no acesso a estado partilhado assume actualmente um papel de destaque no desenvolvimento de software. Trabalhos recentes propõem que tal gestão seja expressa ao nível dos dados, em alternativa à usual centralidade no código. A principal vantagem é o acoplamento da gestão da concorrência com a declaração dos dados, eliminando desse modo a descentralização dos erros de concorrência, facilitando a sua correção. No entanto, as abordagens centradas nos dados existentes pecam por não garantirem a ausência de deadlocks em todos os cenários e/ou exigirem do programador a agregação explícita dos recursos que devem ser avaliados atomicamente. A nossa proposta colmata ambas estas limitações. O programador anota isoladamente que zonas de memória requerem acesso exclusivo, sendo que uma análise estática infere quais dessas devem ser agrupadas e adquiridas atomicamente, e garante que o código gerado é ausente de deadlocks. De modo a aferir-se a eficiência da nossa solução, comparamos o seu desempenho e a sua produtividade relativamente à memória transacional e outras abordagens centrada nos dados.

Delgado, Nuno, and Hervé Paulino. "Uma Abordagem Sistema para o Paralelismo Hierárquico em Arquitecturas Multi-core." INForum 2013 - Atas do 5º Simpósio de Informática. Eds. João Cachopo, and Beatriz Sousa Santos. Évora, Portugal: Escola de Ciências e Tecnologia da Universidade de Évora, 2013. 274-285. Abstract

A decomposição correta de um problema paralelo com base na hierarquia de memória onde irá executar pode levar a ganhos de desempenho significativos durante execução do mesmo. No entanto, os subsistemas de memória das arquiteturas multicore modernas apresentam variadas configurações, em termos das suas organizações hierárquicas e da capacidade dos seus diversos níveis de memória. Existem diversas abordagens que permitem adequar a execução de uma aplicação à estratificação hierárquica da memória,. Contudo estas exigem do programador um conhecimento profundo da arquitetura alvo e de programação paralela em geral. A abordagem apresentada neste artigo contrasta com as demais, transpondo esta responsabilidade para o sistema de execução, colocando sobre a sua alçada a decomposição hierárquica da computação. Nessa medida, ao programador cabe apenas expressar de forma genérica os algoritmos de subdivisão do domínio do problema. Avaliamos o desempenho da nossa abordagem relativamente a outra baseada na usual decomposição horizontal do domínio do problema. Os resultados são bons, apresentando ganhos de performance em aplicações que usufruem do tipo de otimização efetuada e desempenhos equiparáveis nas restantes.