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2014
Ahmad, Mehrbod, Zutshi Aneesh, and Grilo António. "A Vector Space Model Approach for Searching and Matching Product E-Catalogues." Advances in Intelligent Systems and Computing. 2014. 833-842. Abstract
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Carvalho, Carlos, Guilherme Lavareda, Ana Amaral, Carlos Nunes de Carvalho, and Nuno Paulino. "A CMOS micro power switched-capacitor DC-DC step-up converter for indoor light energy harvesting applications." ANALOG INTEGRATED CIRCUITS AND SIGNAL PROCESSING. 78 (2014): 333-351. Abstract

This paper presents a micro power light energy harvesting system for indoor environments. Light energy is collected by amorphous silicon photovoltaic (a-Si:H PV) cells, processed by a switched capacitor (SC) voltage doubler circuit with maximum power point tracking (MPPT), and finally stored in a large capacitor. The MPPT fractional open circuit voltage (V-OC) technique is implemented by an asynchronous state machine (ASM) that creates and dynamically adjusts the clock frequency of the step-up SC circuit, matching the input impedance of the SC circuit to the maximum power point condition of the PV cells. The ASM has a separate local power supply to make it robust against load variations. In order to reduce the area occupied by the SC circuit, while maintaining an acceptable efficiency value, the SC circuit uses MOSFET capacitors with a charge sharing scheme for the bottom plate parasitic capacitors. The circuit occupies an area of 0.31 mm(2) in a 130 nm CMOS technology. The system was designed in order to work under realistic indoor light intensities. Experimental results show that the proposed system, using PV cells with an area of 14 cm(2), is capable of starting-up from a 0 V condition, with an irradiance of only 0.32 W/m(2). After starting-up, the system requires an irradiance of only 0.18 W/m(2) (18 mu W/cm(2)) to remain operating. The ASM circuit can operate correctly using a local power supply voltage of 453 mV, dissipating only 0.085 mu W. These values are, to the best of the authors' knowledge, the lowest reported in the literature. The maximum efficiency of the SC converter is 70.3 % for an input power of 48 mu W, which is comparable with reported values from circuits operating at similar power levels.

Carvalho, Carlos, Guilherme Lavareda, Ana Amaral, Carlos Nunes de Carvalho, and Nuno Paulino. "A CMOS micro power switched-capacitor DC-DC step-up converter for indoor light energy harvesting applications." ANALOG INTEGRATED CIRCUITS AND SIGNAL PROCESSING. 78 (2014): 333-351. Abstract

This paper presents a micro power light energy harvesting system for indoor environments. Light energy is collected by amorphous silicon photovoltaic (a-Si:H PV) cells, processed by a switched capacitor (SC) voltage doubler circuit with maximum power point tracking (MPPT), and finally stored in a large capacitor. The MPPT fractional open circuit voltage (V-OC) technique is implemented by an asynchronous state machine (ASM) that creates and dynamically adjusts the clock frequency of the step-up SC circuit, matching the input impedance of the SC circuit to the maximum power point condition of the PV cells. The ASM has a separate local power supply to make it robust against load variations. In order to reduce the area occupied by the SC circuit, while maintaining an acceptable efficiency value, the SC circuit uses MOSFET capacitors with a charge sharing scheme for the bottom plate parasitic capacitors. The circuit occupies an area of 0.31 mm(2) in a 130 nm CMOS technology. The system was designed in order to work under realistic indoor light intensities. Experimental results show that the proposed system, using PV cells with an area of 14 cm(2), is capable of starting-up from a 0 V condition, with an irradiance of only 0.32 W/m(2). After starting-up, the system requires an irradiance of only 0.18 W/m(2) (18 mu W/cm(2)) to remain operating. The ASM circuit can operate correctly using a local power supply voltage of 453 mV, dissipating only 0.085 mu W. These values are, to the best of the authors' knowledge, the lowest reported in the literature. The maximum efficiency of the SC converter is 70.3 % for an input power of 48 mu W, which is comparable with reported values from circuits operating at similar power levels.

Maiti, B. K., L. B. Maia, K. Pal, B. Pakhira, T. Aviles, I. Moura, S. R. Pauleta, J. L. Nunez, A. C. Rizzi, CD Brondino, S. Sarkar, and J. J. Moura. "One electron reduced square planar bis(benzene-1,2-dithiolato) copper dianionic complex and redox switch by O2/HO(-)." Inorg Chem. 53 (2014): 12799-808. AbstractWebsite

The complex [Ph4P]2[Cu(bdt)2] (1(red)) was synthesized by the reaction of [Ph4P]2[S2MoS2CuCl] with H2bdt (bdt = benzene-1,2-dithiolate) in basic medium. 1(red) is highly susceptible toward dioxygen, affording the one electron oxidized diamagnetic compound [Ph4P][Cu(bdt)2] (1(ox)). The interconversion between these two oxidation states can be switched by addition of O2 or base (Et4NOH = tetraethylammonium hydroxide), as demonstrated by cyclic voltammetry and UV-visible and EPR spectroscopies. Thiomolybdates, in free or complex forms with copper ions, play an important role in the stability of 1(red) during its synthesis, since in its absence, 1(ox) is isolated. Both 1(red) and 1(ox) were structurally characterized by X-ray crystallography. EPR experiments showed that 1(red) is a Cu(II)-sulfur complex and revealed strong covalency on the copper-sulfur bonds. DFT calculations confirmed the spin density delocalization over the four sulfur atoms (76%) and copper (24%) atom, suggesting that 1(red) has a "thiyl radical character". Time dependent DFT calculations identified such ligand to ligand charge transfer transitions. Accordingly, 1(red) is better described by the two isoelectronic structures [Cu(I)(bdt2, 4S(3-,)*)](2-) <--> [Cu(II)(bdt2, 4S(4-))](2-). On thermodynamic grounds, oxidation of 1(red) (doublet state) leads to 1(ox) singlet state, [Cu(III)(bdt2, 4S(4-))](1-).

Kasthurirangan, S., J. K. Saha, A. N. Agnihotri, A. Banerjee, A. Kumar, D. Misra, J. P. Santos, A. M. Costa, P. Indelicato, T. K. Mukherjee, and L. C. Tribedi. "High-resolution x-ray spectra from highly charged Si, S and Cl ions showing evidence of fluorescence active resonant states." Journal of Physics: Conference Series. 488 (2014): 132027-2. AbstractWebsite

We have measured the x-ray spectra from highly charged Si, S and Cl ions in collisions with thin foils using a high-resolution x-ray spectrometer. The observed lines have been assigned to various transitions in H-, He- and Li-like ions. For proper identification of line positions, the theoretical calculations have been carried out using a state-of-the-art MCDF code including QED effects, with which the experimental data is in excellent agreement. We have also observed, for the first time, x-rays arising out of the decay of long-lived resonant states in the He-like ions of each species. Details will be presented.

Amado, M. P., F. Pinho, P. Faria, and I. Ramalhete. "Eco-wall modular solutions for buildings." 9th International Masonry Conference. Guimaraes - ISBN: 978-972-8692-87-2: ICM; Universidade do Minho, 2014.
Amado, Miguel, Fernando Pinho, Paulina Faria, and Inês Ramalhete. "Eco-wall modular solutions for buildings." IMC2014 - 9th International Masonry Conference 2014. Universidade do Minho, Guimarães 2014.
Pinho, Fernando F. S., Válter J. G. Lúcio, Luís Moura, Nuno Travassos, and Inês Almeida. "Evaluation of cover deviation and resistance of steel anchorages in masonry walls." IMC2014 - 9th International Masonry Conference 2014. Universidade do Minho, Guimarães 2014.
Bernardo, Vasco, André Oliveira, Filipe Amarante dos Santos, and Corneliu Cismasiu. "Vulnerabilidade e reforço sísmico de uma passagem superior pedonal pré-fabricada." 5as Jornadas Portuguesas de Engenharia de Estruturas. Lisboa, Portugal : LNEC, 2014.
Soldado, Fábio, Fernando Alexandre, and Hervé Paulino. "Towards the Transparent Execution of Compound OpenCL Computations in Multi-CPU/Multi-GPU Environments." Euro-Par 2014 International Workshops, Revised Selected Papers, Part I. Porto, Portugal: Springer, 2014. Abstract

Currentcomputationalsystemsareheterogeneousbynature, featuring a combination of CPUs and GPUs. As the latter are becoming an established platform for high-performance computing, the focus is shifting towards the seamless programming of the heterogeneous systems as a whole. The distinct nature of the architectural and execution models in place raise several challenges, as the best hardware configuration is behavior and data-set dependent. In this paper, we focus the execution of compound computations in multi-CPU/multi-GPU environments, in the scope of Marrow algorithmic skeleton framework, the only, to the best of our knowledge, to support skeleton nesting in GPU computing. We address how these computations may be efficiently scheduled onto the target hardware, and how the system may adapt itself to changes in the CPU’s load and in the input data-set.

Poggi, F., and M. P. Amado. " Conceito de região funcional no contexto energético do território - espaço de cooperação rural - urbano." PLURIS 2014. FCG - Lisboa, PT: FA UL, 2014.
Fliedel, C., V. Rosa, C. I. M. Santos, P. J. Gonzalez, R. M. Almeida, C. S. B. Gomes, P. T. Gomes, M. A. N. D. A. Lemos, G. Aullón, R. Welter, and T. Avilés. "Copper(ii) complexes of bis(aryl-imino)acenaphthene ligands: Synthesis, structure, DFT studies and evaluation in reverse ATRP of styrene." Dalton Transactions. 43.34 (2014): 13041-13054. AbstractWebsite
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Cismasiu, Corneliu, Filipe Amarante dos Santos, and Ana Rodrigues. "Experimental and FE updating techniques for the unseating vulnerability assessment of a footbridge structure." The 4th International Conference on Dynamics, Vibration and Control. Shanghai, China: Shanghai Institute of Applied Mathematics and Mechanics, 2014.
Acker, Arnold Van, Carlos Chastre, Barry Crisp, David Fernandez, Válter Lúcio, Kim S. Elliott, Simon Hughes, George Jones, Holger Karutz, Ronald Klein-Holte, Stef Maas, Marco Menegotto, Spyros Tsoukantas, and Pieter van der Zee fib Bulletin 74. Planning and design handbook on precast building structures. fib bulletin. Lausanne: International Federation for Structural Concrete (fib), 2014. AbstractWebsite

In 1994 fib Commission 6: Prefabrication edited a successful Planning and Design Handbook that ran to approximately 45,000 copies and was published in Spanish and German.Nearly 20 years later Bulletin 74 brings that first publication up to date. It offers a synthesis of the latest structural design knowledge about precast building structures against the background of 21st century technological innovations in materials, production and construction. With it, we hope to help architects and engineers achieve a full understanding of precast concrete building structures, the possibilities they offer and their specific design philosophy. It was principally written for non-seismic structures.

The handbook contains eleven chapters, each dealing with a specific aspect of precast building structures.
The first chapter of the handbook highlights best practice opportunities that will enable architects, design engineers and contractors to work together towards finding efficient solutions, which is something unique to precast concrete buildings.
The second chapter offers basic design recommendations that take into account the possibilities, restrictions and advantages of precast concrete, along with its detailing, manufacture, transport, erection and serviceability stages.
Chapter three describes the precast solutions for the most common types of buildings such as offices, sports stadiums, residential buildings, hotels, industrial warehouses and car parks. Different application possibilities are explored to teach us which types of precast units are commonly used in all those situations.
Chapter four covers the basic design principles and systems related to stability. Precast concrete structures should be designed according to a specific stability concept, unlike cast in-situ structures.
Chapter five discusses structural connections.
Chapters six to nine address the four most commonly used systems or subsystems of precast concrete in buildings, namely, portal and skeletal structures, wall-frame structures, floor and roof structures and architectural concrete facades.
In chapter ten the design and detailing of a number of specific construction details in precast elements are discussed, for example, supports, corbels, openings and cutouts in the units, special features related to the detailing of the reinforcement, and so forth.
Chapter eleven gives guidelines for the fire design of precast concrete structures. The handbook concludes with a list of references to good literature on precast concrete construction.

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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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.

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.
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.