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2014
Chastre, Carlos. "Materiais e tecnologias de reforço de estruturas de betão - potencialidade e limitações." REHABEND 2014 - Congresso Latinoamericano "Patología de la construcción, Tecnología de la rehabilitacíon y gestión del patrimonio". Santander 2014. Abstractcarlos_chastre__-_rehabend2014_-_santander.pdf

O desenvolvimento da engenharia de estruturas tem tido grandes avanços nas últimas décadas, baseados em novos meios de cálculo e na investigação em novos materiais e tecnologias a eles associadas. Por sua vez, as atividades de reparação e reforço têm vindo a incrementar devido ao envelhecimento e à degradação das estruturas de betão, o que consequentemente tem dado origem ao aparecimento de novos materiais e tecnologias de reparação e reforço de estruturas. A utilização destes novos materiais na construção tem vindo a substituir outros materiais e técnicas existentes, requerendo, no entanto, mais estudos sobre o seu real comportamento quer em termos de caracteristicas mecânicas quer em termos de durabilidade.

Hendrickx, Christophe, Ricardo Araújo, and Octávio Mateus. "The nonavian theropod quadrate II: systematic usefulness, major trends and cladistic and phylogenetic morphometrics analyses." PeerJ PrePrints. 2 (2014): e380v2. AbstractWebsite

The skull-bone quadrate in nonavian theropods is very diverse morphologically alongside the disparity of the group as a whole. However this disparity has been underestimated for taxonomic purposes. In order to evaluate the phylogenetic potential and investigate the evolutionary transformations of the quadrate, we conducted a Catalano-Goloboff phylogenetic morphometric analysis as well as a cladistic analysis using 98 discrete quadrate related characters. The cladistic analysis provides a fully resolved tree mirroring to some degree the classification of nonavian theropods. The quadrate morphology by its own provides a wealth of data with strong phylogenetic signal and allows inference of major trends in the evolution of this bone. Important synapomorphies include: for Abelisauroidea, a lateral ramus extending to the ectocondyle; for Tetanurae, the absence of the lateral process; for Spinosauridae, a medial curvature of the ventral part of the pterygoid ramus occurring just above the mandibular articulation; for Avetheropoda, an anterior margin of the pterygoid flange formed by a roughly parabolic margin; and for Tyrannosauroidea, a semi-oval pterygoid flange shape in medial view. The Catalano-Goloboff phylogenetic morphometric analysis reveals two main morphotypes of the mandibular articulation of the quadrate linked to function. The first morphotype, characterized by an anteroposteriorly broad mandibular articulation with two ovoid/subcircular condyles roughly subequal in size, is found in Ceratosauria, Tyrannosauroidea and Oviraptorosauria. This morphotype allows a very weak displacement of the mandible laterally. The second morphotype is characterized by an elongate and anteroposteriorly narrow mandibular articulation and a long and parabolic/sigmoid ectocondyle. Present in Megalosauroidea, Carcharodontosauridae and Dromaeosauridae, this morphotype permits the lower jaw rami to be displaced laterally when the mouth opened.

Restani, Rita B., Joao Conde, Pedro V. Baptista, Maria Teresa Cidade, Ana M. Bragança, Jorge Morgado, Ilídio J. Correia, Ana Aguiar-Ricardo, and Vasco D. B. Bonifácio. "Polyurea dendrimer for efficient cytosolic siRNA delivery." 4.97 (2014): 54872-54878. Abstract
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Domingo, A., D. Specklin, V. Rosa, S. Mameri, V. Robert, and R. Welter. "Probing the influence of the ligands on the magnetism of dinuclear manganese, iron, and chromium complexes supported by aroylhydrazone." European Journal of Inorganic Chemistry.15 (2014): 2552-2560. AbstractWebsite
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Ceia, T. F., A. G. Silva, C. S. Ribeiro, JV Pinto, MH Casimiro, A. M. Ramos, and J. Vital. "PVA composite catalytic membranes for hyacinth flavour synthesis in a pervaporation membrane reactor." Catalysis Today. 236 (2014): 98-107. Abstract
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Figueiredo, Maria-Ondina, Teresa P. Silva, Joao P. Veiga, Maria-Joao Batista, Eduardo Salas-Colera, and Daniel P. de Oliveira. "Selenium Speciation in Waste Materials From an Exhausted Iberian Pyrite Belt Mine." Journal of Materials Science Research. 3.4 (2014): p22. Abstract

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Duarte, A. G., C. M. Cordas, JJG Moura, and I. Moura. "Steady-state kinetics with nitric oxide reductase (NOR): New considerations on substrate inhibition profile and catalytic mechanism." Biochimica et Biophysica Acta - Bioenergetics. 1837.3 (2014): 375-384. AbstractWebsite
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Passos, F., M. H. Fino, and E. R. Moreno. "Analytical Characterization of Variable Width Integrated Spiral Inductors." International Journal of Electronics and Telecommunications (2014): 7377.
Gião, Rita, Válter Lúcio, and Carlos Chastre. "Assessing the behaviour of RC beams subject to significant gravity loads under cyclic loads." Engineering Structures. 59 (2014): 512-521. AbstractWebsite

Gravity loads can affect a reinforced concrete structure’s response to seismic actions, however, traditional procedures for testing the beam behaviour do not take this effect into consideration. An experimental campaign was carried out in order to assess the influence of the gravity load on RC beam connection to the column subjected to cyclic loading. The experiments included the imposition of a conventional quasi-static test protocol based on the imposition of a reverse cyclic displacement history and of an alternative cyclic test procedure starting from the gravity load effects. The test results are presented, compared and analysed in this paper. The imposition of a cyclic test procedure that included the gravity loads effects on the RC beam ends reproduces the demands on the beams’ critical zones more realistically than the traditional procedure. The consideration of the vertical load effects in the test procedure led to an accumulation of negative (hogging) deformation. This phenomenon is sustained with the behaviour of a portal frame system under cyclic loads subject to a significant level of the vertical load, leading to the formation of unidirectional plastic hinges. In addition, the hysteretic behaviour of the RC beam ends tested was simulated numerically using the nonlinear structural analysis software – OpenSees. The beam–column model simulates the global element behaviour very well, as there is a reasonable approximation to the hysteretic loops obtained experimentally.

de Melo, J. L. A., Querido F., Paulino N., and Goes J. A 0.4-V 410-nW opamp-less continuous-time ΣΔ modulator for biomedical applications. IEEE International Symposium on Circuits and Systems (ISCAS). Melbourne, Australia: IEEE, 2014.
Polcyn, M. J., LL Jacobs, C. Strganac, O. Mateus, TS Myers, S. May, R. Araújo, AS Schulp, and ML Morais. "Geological and paleoecological setting of a marine vertebrate bonebed from the Lower Maastrichtian at Bentiaba, Angola." Secondary Adaptation of Tetrapods to Aquatic Life. Washington DC, USA 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.