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2012
Mateus, O., M. J. Polcyn, LL Jacobs, R. Araújo, AS Schulp, J. Marinheiro, B. Pereira, and D. Vineyard Cretaceous amniotes from Angola: dinosaurs, pterosaurs, mosasaurs, plesiosaurs, and turtles. V Jornadas Internacionales sobre Paleontología de Dinosaurios y su Entorno. Salas de los Infantes, Burgos, 2012. Abstractmateus_et_al_2012_amniotes_from_angola_cretaceous_amniotes_from_angola_dinosaurs_pterosaurs_mosasaurs.pdf

Although rich in Cretaceous vertebrate fossils, prior to 2005 the amniote fossil record of Angola was poorly known. Two horizons and localities have yielded the majority of the vertebrate fossils collected thus far; the Turonian Itombe Formation of Iembe in Bengo Province and the Maastrichtian Mocuio Formation of Bentiaba in Namibe Province. Amniotes of the Mesozoic of Angola are currently restricted to the Cretaceous and include eucryptodire turtles, plesiosaurs, mosasaurs, pterosaurs, and dinosaurs. Recent collecting efforts have greatly expanded our knowledge of the amniote fauna of Angola and most of the taxa reported here were unknown prior to 2005.

Silva, M. A. G., H. C. Biscaia, and C. Chastre Degradação da aderência entre compósitos de GFRP e betão devido a condições ambientais severas. Betão Estrutural 2012. Porto: FEUP, 2012. Abstractsilva2012bich_-_be2012_-_feup.pdf

A degradação da ligação entre compósitos de matriz polimérica reforçada por fibras (FRP) e o betão é uma das principais causas de possível rotura das vigas e lajes de betão armado reforçadas
externamente por compósitos de FRP. Desde há mais de 10 anos que se estuda, por isso, na UNL o
comportamento dessa ligação, integrado em programa mais alargado de estudo da durabilidade deste tipo de reforço, especialmente quando sujeito a condições ambientais severas que se simulam por processos artificialmente acelerados no laboratório. Em particular a degradação da aderência e o possível descolamento precoce do reforço têm sido modelados física e computacionalmente com principal incidência no uso de fibras de vidro (GFRP) e resina epoxídica. Nesta comunicação mostram-se resultados obtidos em termos de capacidade de carga, força transmitida ao reforço e tensões de aderência após envelhecimentos de pequenas vigas de betão armado (BA) por ciclos de nevoeiro salino, ciclos seco/molhado em solução salina, ciclos de temperatura entre +7,5ºC e +47,5ºC e gelo-degelo de -10ºC a +30ºC. Faz-se recomendação quanto à extensão máxima para diferentes envelhecimentos. Apresenta-se comparação entre resultados de modelação numérica e experimental.

Azevedo, S. G., K. Godivan, H. Carvalho, and V. Cruz-Machado. "Deployment of radio frequency identification technology in healthcare organizations." POMS 23rd Annual Conference. Chicago, Illinois, U.S.A. 2012. Abstract

The Radio Frequency Identification (RFID) technology is a wireless technology that uses transmitted radio signals to tag, recognize, track and trace the movement of an item automatically. The study of this technology is actually considered a hot topic in all scientific areas and has been described as a major enabling technology for the automation of many processes. Although it is not a new technology it has only recently come to the awareness of the public and widely used in many sectors and particularly in the Healthcare. This paper aims to illustrate the deployment of RFID technology in Healthcare, more precisely in infant security systems. A case study about the experience of three hospitals and one RFID technology provider is presented to highlight the main architectural characteristics, functionality, and advantages associated to its deployment. After the case studies analysis it is possible to state that the infant security systems, using the RFID technology, are not so different among research case studies: they involve RFID tagging patients, they are easy to use not requiring an extensive training and also they are installed with an interface with others security systems.

A.P. Fonseca, T. Batista, Teodoro O. M. N. D. DESIGN AND CHARACTERIZATION OF REFRIGERANT REFERENCE LEAKS. PTDC/EME-MFE/098738/2008., 2012.13_2012_evc12.pdf
Ferraz, Ricardo, Luís C. Branco, Isabel M. Marrucho, João M. M. Araújo, Luis Paulo N. Rebelo, Manuel Nunes da Ponte, Cristina Prudêncio, João Paulo Noronha, and Zeljko Petrovski. "Development of novel ionic liquids based on ampicillin." Med. Chem. Commun.. 3 (2012): 494.Development of Novel Ionic Liquids Based on Ampicillin.pdf
Biscaia, Hugo C., Carlos Chastre, and Manuel A. G. Silva. "Double shear tests to evaluate the bond strength between GFRP/concrete elements." Composite Structures. 94 (2012): 681-694. AbstractWebsite

Externally bonded reinforced systems have been widely used in civil engineering. However, the problems associated with bond between structural elements are not yet fully solved. As a consequence, many researchers have been proposing tests and techniques to standardize procedures and reach better agreement for design purposes. In the present paper, an experimental program is described that was developed to characterize the glass FRP/concrete interface by double shear tests made on 15 cm side cubes with GFRP bonded on two opposite faces. The GFRP wrap had two layers applied by the wet lay-up technique and three classes of concrete were considered. With the support of the experimental program, cohesion and friction angle for GFRP–concrete interfaces were found leading to different envelope failure laws, based on the Mohr–Coulomb failure criterion for each concrete class, capable of predicting GFRP debonding. Results are discussed.

Rybarczyk, Y., and Mestre D. "Effect of temporal organization of the visuo-locomotor coupling on the predictive steering." Frontiers in Perception Science. 3.239 (2012): 10.3389/fpsyg.2012.00239.copy.pdf
Dias, Ricardo J., Tiago M. Vale, and João M. Lourenço. "Efficient Support for In-Place Metadata in Transactional Memory." Proceedings of the 18th International Euro-Par Conference on Parallel Processing. {Euro-Par}. Berlin, Heidelberg: Springer-Verlag, 2012. Abstracteuropar12.pdf

Software Transactional Memory (STM) algorithms correctness rely on metadata associated with the memory locations accessed during the transaction life-time. STM implementations may store this metadata either in-place, by wrapping the memory cells in a container that includes the memory cell itself and the corresponding metadata, or out-place, by resorting to a mapping function that associates the memory cell address to an external table with the corresponding metadata. The implementation techniques for these two approaches are very different and each STM framework is usually biased towards one of them, only allowing the efficient implementation of algorithms that fall into the appropriate category, and inhibiting the fair comparison with STM algorithms falling into the other. In this paper we introduce a technique that supports the use of in-place metadata without requiring to wrap memory cells, thus providing STM algorithms with direct access to the transactional metadata and overcoming the bias. The proposed technique is available as an extension to the DeuceSTM framework and allows the efficient implementation of a wide range of STM algorithms, thus enabling their fair (unbiased) comparison in a common STM infrastructure. We illustrate the benefits of our approach by analyzing its impact in two popular TM algorithms with two different transactional workloads, TL2 and multi-versioning, which bias to out-place and in-place respectively.

Queirós, Raquel B., J. P. Noronha, P. V. S. Marques, and Goreti M. F. Sales. "Emerging (bio)sensing Technology for Assessing and Monitoring Freshwater Contamination – Methods and Applications." Ecological Water Quality - Water Treatment and Reuse. InTech, 2012. 65-94.Emerging Bio Sensing Technology for Assessing and Monitoring Freshwater Contamination Methods and Applications.pdf
E. Piveta, A. Moreira, M. Pimenta, J. Araújo, P. Guerreiro, and T. Price. "An Empirical Study of Aspect-Oriented Metrics." Science of Computer Programming (2012). Abstract

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Afonso, J., D. Martins, I. Catarino, R. Patrício, A. Rocaboy, M. Linder, T. Tirolien, and G. Bonfait "Energy storage unit using cryogenic liquids for integration in cryocoolers". ICEC 24. Fukuoka, Japan, 2012.
Bras, Joana L. A., Ana Luisa Carvalho, Aldino Viegas, Shabir Najmudin, Victor D. Alves, Jose A. M. Prates, Luis M. A. Ferreira, Maria J. Romao, Harry J. Gilbert, and Carlos M. G. A. Fontes. "Escherichia coli expression, purification, crystallization, and structure determination of bacterial cohesin-dockerin complexes." Methods in enzymology. Vol. 510. 2012. 395-415. Abstract

Cellulosomes are highly efficient nanomachines that play a fundamental role during the anaerobic deconstruction of complex plant cell wall carbohydrates. The assembly of these complex nanomachines results from the very tight binding of repetitive cohesin modules, located in a noncatalytic molecular scaffold, and dockerin domains located at the C-terminus of the enzyme components of the cellulosome. The number of enzymes found in a cellulosome varies but may reach more than 100 catalytic subunits if cellulosomes are further organized in polycellulosomes, through a second type of cohesin-dockerin interaction. Structural studies have revealed how the cohesin-dockerin interaction mediates cellulosome assembly and cell-surface attachment, while retaining the flexibility required to potentiate catalytic synergy within the complex. Methods that might be applied for the production, purification, and structure determination of cohesin-dockerin complexes are described here. Copyright 2012 Elsevier Inc. All rights reserved.

Myers, TS, NJ Tabor, LL Jacobs, and O. Mateus. "Estimating soil pCO2 using paleosol carbonates: implications for the relationship between primary productivity and faunal richness in ancient terrestrial ecosystems." Paleobiology. 38.4 (2012): 585-604. Abstractmyers_et_al_2012_estimating_soil_paleosols_portugal.pdf

In this paper we present a method for estimating soil pCO2 in ancient environments using the measured carbon-isotope values of pedogenic carbonates and plant-derived organic matter. The validity of soil pCO2 estimates proves to be highly dependent on the organic δ13C values used in the calculations. Organic matter should be sourced from the same paleosol profiles as sampled carbonates to yield the most reliable estimates of soil pCO2. In order to demonstrate the potential use of soil pCO2 estimates in paleoecological and paleoenvironmental studies, we compare samples from three Upper Jurassic localities. Soil pCO2 estimates, interpreted as a qualitative indicator of primary paleoproductivity, are used to rank the Late Jurassic terrestrial environments represented by the Morrison Formation in western North America, the informally named Lourinhã formation in Western Europe, and the Stanleyville Group in Central Africa. Because modern terrestrial environments show a positive correlation between primary productivity and faunal richness, a similar relationship is expected in ancient ecosystems. When the relative paleoproductivity levels inferred for each study area are compared with estimates of dinosaur generic richness, a positive correlation emerges. Both the Morrison and Lourinhã formations have high inferred productivity levels and high estimated faunal richness. In contrast, the Stanleyville Group appears to have had low primary productivity and low faunal richness. Paleoclimatic data available for each study area indicate that both productivity and faunal richness are positively linked to water availability, as observed in modern terrestrial ecosystems.

Barišić, Ankica, Vasco Amaral, Miguel Goulão, and Bruno Barroca. "Evaluating the Usability of Domain-Specific Languages." Formal and Practical Aspects of Domain-Specific Languages: Recent Developments. Ed. Marjan Mernik. IGI Global, 2012. Abstract

We can regard Domain-Specific Languages (DSLs) as User Interfaces (UIs) because they bridge the gap
between the domain experts and the computation platforms. Usability of DSLs by domain experts is a key
factor for their successful adoption. The few reports supporting improvement claims are persuasive, but
mostly anecdotal. Systematic literature reviews show that evidences on the effects of the introduction of
DSLs are actually very scarce. In particular, the evaluation of usability is often skipped, relaxed, or at
least omitted from papers reporting the development of DSLs. The few exceptions mostly take place at
the end of the development process, when fixing problems is already too expensive. A systematic
approach, based on techniques for the experimental evaluation of UIs, should be used to assess suitability
of new DSLs. This chapter presents a general experimental evaluation model, tailored for DSLs’
experimental evaluation, and instantiates it in several DSL’s evaluation examples.

Teixeira, Paula, Helena Lopes, Ibrahim Gulyurtlu, Nuno Lapa, and Pedro Abelha. "Evaluation of slagging and fouling tendency during biomass co-firing with coal in a fluidized bed." Biomass & Bioenergy. 39 (2012): 192-203. AbstractWebsite

Over the last decades, several indices based on ash chemistry and ash fusibility have been used to predict the ash behaviour during coal combustion, namely, its tendency for slagging and fouling. However, due to the physical–chemical differences between coals and biomass, in this work only the applicability of an ash fusibility index (AFI) to the combustion and co-combustion of three types of biomass (straw pellets, olive cake and wood pellets) with coals was evaluated. The AFI values were compared with the behaviour of ash during combustion in a pilot fluidized bed and a close agreement was observed between them. For a better understanding of the mechanisms associated with bed ash sintering, they were evaluated by SEM/EDS and the elements present on the melted ash were identified. Evidences of different sintering mechanisms were found out for the fruit biomass and herbaceous biomass tested, depending on the relative proportions of problematic elements. The particles deposited on a fouling probe inserted in the FBC were analyzed by XRD and the differences between the compounds identified allowed concluding that the studied biomasses present different tendencies for fouling. Identification of KCl and K2SO4 in the deposits confirmed the higher tendency for fouling of fruit biomass tested rather than wood pellets.

Tschopp, E., and O. Mateus. "Evidence for presence of clavicles and interclavicles in sauropod dinosaurs and its implications on the furcula-clavicle homology." Journal of Vertebrate Paleontology, Program and Abstracts, 2012, 184. ISSN 1937-2809 (2012): 184. Abstracttschopp__mateus_2012_interclavicles_clavicles_svp_2012_abstract.pdf

Clavicles and interclavicles are plesiomorphically present in Reptilia. However, several groups show reduction or even loss of these elements. Crocodylimorpha, e.g., lost the clavicles, whereas dinosaurs are generally interpreted to only preserve the clavicles, the theropod furcula representing an unique case of fused clavicles. In sauropods, reports of clavicles are relatively frequent in non-titanosauriforms. These elements are elongated, curved, and rather stout bones with a spatulate and a bifurcate end. However, they were always found as single bones, and differ from the relatively short and unbifurcated clavicles found articulated with the scapulae of basal sauropodomorphs.
Elements from the Howe Quarry (Late Jurassic; Wyoming, USA) shed new light on these interpretations. Besides the elongated, curved bones (herein named morphotype A), also pairs of symmetric, L-shaped bones were recovered (morphotype B), associated with diplodocid dorsal and cervical vertebrae. Elements resembling morphotype B - articulated between the scapulae - have recently been reported from a diplodocid found near Tensleep, Wyoming. Taphonomic evidence, as well as the fact that they were preserved in symmetrical pairs, therefore implies that morphotype B represents the true sauropod clavicles.
Contrary to earlier reports, morphotype A elements from the Howe Quarry, as well as of previously reported specimens show a symmetry plane following the long axis of the elements. It is thus possible that the morphotype A elements were single bones from the body midline. The only such element present in the pectoral girdle of tetrapods are the interclavicle and the furcula. Comparison with crocodilian and lacertiform interclavicles indicates that the bifurcate end of the sauropod elements might represent the reduced transverse processes of the anterior end, and the spatulate end would have covered the coracoids or sternal plates ventrally.
The presence of both clavicles and interclavicles in the pectoral girdle stiffens the anterior trunk, and enhances considerably its stability. Such an enforcement might have been needed in diplodocids due to the strong lateral forces induced to the fore-limbs by the posteriorly placed center of mass (due to shorter fore- than hind-limbs), as well as lateral movements of the enormously elongated necks and tails. The absence of clavicles and interclavicles in titanosauriforms coincides with the development of wide-gauge locomotion style.
The presence of interclavicles in sauropods supports the recently proposed homology of the furcula with the interclavicle, instead of representing fused clavicles. Interclavicles were thus not lost, but may have remained cartilaginous or have yet to be found in basal dinosauriforms.

Herrera, J., Rivera P. Salas, R. Vargas, I. Macia, R. Pinho, A. Garcia, J. Araújo, and K. Breitman An Exploraty Study of Aspect-Oriented Requirement Engineering Tools. 26º Simpósio Brasileiro de Engenharia de Software (SBES). Natal, Brazil: IEEE digital library, 2012.
Cunha, Jácome, João Paulo Fernandes, Jorge Mendes, and João Saraiva. "Extension and Implementation of ClassSheet Models." Proceedings of the 2012 IEEE Symposium on Visual Languages and Human-Centric Computing. VLHCC '12. Washington, DC, USA: IEEE Computer Society, 2012. 19-22. Abstractvlhcc12.pdf

n this paper we explore the use of models in the context of spreadsheet engineering. We review a successful spreadsheet modeling language, whose semantics we further extend. With this extension we bring spreadsheet models closer to the business models of spreadsheets themselves. An addon for a widely used spreadsheet system, providing bidirectional model-driven spreadsheet development, was also improved to include the proposed model extension.

Lucas, D., H. C. Biscaia, M. A. G. Silva, and C. Chastre Factores que influenciam o desempenho da ligação GFRP/betão. Betão Estrutural 2012. Porto: FEUP, 2012. Abstractlucas2012bisich_-_be2012.pdf

Os compósitos de FRP podem descolar prematuramente da superfíce de betão, isto é, antes de esgotada a sua resistência elástica. Esta situação é mais provável se não forem tidos em conta factores como o tipo de preparação da superfície, a exposição a acção ambiental severa, e a resistência do próprio betão. Com o objectivo de analisar a influência de parte destes factores no desempenho da ligação compósito de fibra de vidro (GFRP) e betão, empreendeu-se uma campanha experimental baseada em ensaios de corte duplo. Os resultados permitiram determinar e comparar as forças máximas transmitidas ao GFRP e tensões de aderência máxima para diferentes tratamentos de superfície e condições de envelhecimento. Foram também determinadas aproximações para curvas de tensão de aderência vs. deslizamento (bond-slip). Os resultados obtidos são contrastados com resultados obtidos por modelação numérica.

Acker, Arnold Van, Carlos Chastre, Andrzej Cholewicky, Barry Crisp, Válter Lúcio, Kim S. Elliott, Björn Engström, Antonello Gasperi, Arto Suikka, Spyros Tsoukantas, Jan Vambersky, and John Vantomme fib Bulletin 63. Design of precast concrete structures against accidental actions. fib bulletin. Lausanne: Fédération internacionale du béton (fib), 2012. AbstractWebsite

Since the 1980’s, several buildings throughout the world have been subject to gas explosions, impact by cars or airplanes, or car bomb attacks. In many cases the effect of the impact or explosion has been the failure of a critical structural member at the perimeter of the building. After the failure, the load supported by that member could not be redistributed and part or all of the structure has collapsed in a progressive manner. The phenomenon that occurs when local failure is not confined to the area of initial distress, and spreads horizontally and/or vertically through the structure, is termed progressive collapse.

Progressive collapse is a relatively rare event, as it requires both an accidental action to cause local damage and a structure that lacks adequate continuity, ductility, and redundancy to prevent the spread of damage. It is technically very difficult and economically prohibitive to design buildings for absolute safety. However it is possible to construct precast concrete buildings that afford an acceptable degree of safety with regard to accidental actions.

A structure is normally designed to respond properly, without damage, under normal load conditions, but local and/or global damages cannot be avoided under the effect of an unexpected, but moderate degree of accidental overload. Properly designed and constructed structures usually possess reasonable probability not to collapse catastrophically under such loads, depending on different factors, for example: the type of loading; the degree and the location of accidental loading in regard to the structure and its structural members; the type of structural system, the construction technology, and the spans between structural vertical members, etc.

No structure can be expected to be totally resistant to actions arising from an unexpected and extreme cause, but it should not be damaged to an extent that is disproportionate to the original cause.

The aim of fib Bulletin 63 is to summarize the present knowledge on the subject and to provide guidance for the design of precast structures against progressive collapse. This is addressed in terms of (a) the classification of the actions, (b) their effect on the structural types, (c) the strategies to cope with such actions, (d) the design methods and (e) some typical detailing, all supplemented with illustrations from around the world, and some model calculations.

Malheiro, A. "Finite derivation type for semilattices of semigroups." Semigroup Forum. 84 (2012): 515-526. AbstractWebsite

In this paper we investigate how the combinatorial property finite derivation type (FDT) is preserved in a semilattice of semigroups. We prove that if S=S[Y,S_α] is a semilattice of semigroups such that Y is finite and each S_α (α∈Y) has FDT, then S has FDT. As a consequence we can show that a strong semilattice of semigroups S[Y,S_α,λ_{α,β}] has FDT if and only if Y is finite and every semigroup S α (α∈Y) has FDT.

Casimiro, Ana Cristina, and César Rodrigo. "First variation formula and conservation laws in several independent discrete variables." J. Geom. Phys.. 62 (2012): 61-86. Abstract

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Casimiro, Ana Cristina, and César Rodrigo. "First variation formula for discrete variational problems in two independent variables." Rev. R. Acad. Cienc. Exactas Fís. Nat., Ser. A Mat., RACSAM. 106 (2012): 111-135. Abstract

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