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2012
Bahubalindruni, Ganga, Candido Duarte, Vitor Grade Tavares, Pedro Barquinha, Rodrigo Martins, Elvira Fortunato, Pedro Guedes de Oliveira, and Ieee. "Multipliers with Transparent a-GIZO TFTs using a Neural Model." 2012 20th Telecommunications Forum (Telfor) (2012): 955-958. AbstractWebsite
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Duarte, AP, JF Coelho, JC Bordado, M. T. Cidade, and MH Gil. "Surgical adhesives: systematic review of the main types and development forecast." 37.8 (2012): 1031-1050. Abstract
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Li, L., P. S. Lopes, V. Rosa, C. A. Figueira, M. A. N. D. A. Lemos, M. T. Duarte, T. Avilés, and P. T. Gomes. "Synthesis and structural characterisation of (aryl-BIAN)copper(i) complexes and their application as catalysts for the cycloaddition of azides and alkynes." Dalton Transactions. 41.17 (2012): 5144-5154. AbstractWebsite
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Dias, Ricardo Jorge, Dino Distefano, João Costa Seco, and João Manuel Lourenço. "Verification of Snapshot Isolation in Transactional Memory Java Programs." Proceedings of the 26th European Conference on Object-Oriented Programming. {ECOOP}. Beijing, China 2012. Abstractecoop12.pdf

This paper presents an automatic verification technique for transactional memory Java programs executing under snapshot isolation level. We certify which transactions in a program are safe to execute under snapshot isolation without triggering the write-skew anomaly, opening the way to run-time optimizations that may lead to considerable performance enhancements. Our work builds on a novel deep-heap analysis technique based on separation logic to statically approximate the read- and write-sets of a transactional memory Java program. We implement our technique and apply our tool to a set of micro benchmarks and also to one benchmark of the STAMP package. We corroborate known results, certifying some of the examples for safe execution under snapshot isolation by proving the absence of write-skew anomalies. In other cases our analysis has identified transactions that potentially trigger previously unknown write-skew anomalies.>

Valtchev, {Stanimir Stoyanov}, and DEE Group Author. "High frequency wireless energy for improving the EV autonomy." International Symposium on Electric Vehicle and 4-th Annual Conference of Polish Society for Environment Friendly Vehicles. 2012. 6. Abstract

There have been many and very significant advances in the Wireless Power Transfer, resulting up to now in flexible and safe battery charging eliminating the necessity of power cables. The relatively low frequencies (tens of kilohertz) applied for those {"}classical{"} chargers are already well developed. A {"}new{"} technology appeared now that makes possible to apply a strong magnetic resonant coupling. Similar experiments were applied by N. Tesla more than a hundred years ago but now the researchers are capable to reach much higher frequencies. To achieve the necessary high level of magnetic field coupling it is essential to allow high levels of electric current intensity inside the resonant loops. In this article the achievement of highest magnetic field is analysed and experimented. Some results are discussed based on the choice of the resonant loop type and construction. The applications in the on-line energy supply for the EV are one of the aimed goals. The other goal may be the future more efficient induction machine.

Valtchev, {Stanimir Stoyanov}, {Jorge Joaquim} Pamies-Teixeira, {Rosa Maria Mendes} Miranda, {Telmo Jorge Gomes dos} Santos, and DEE Group Author. "New Methodology for Structural Health Monitoring of GLARE in Ships." Proceedings ICEM15. 2012. 1-8. Abstract
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Valtchev, {Stanimir Stoyanov}, and DEE Group Author. "R&D of an thermoelectric system - An innovative Linear Fresnel Reflector." MATCHMAKING RESEARCH Conference. 2012. 1-5. Abstract

The research on the solar concentrating equipment is intensified in the recent years in many scientific and industry groups and institutions. This growing interest is based mainly on the higher efficiency and lower investment in material that is typical for this solar technology. This work started not to answer a market problem but with the idea of development a new application for an domestic size collector of line-focussing Fresnel collector. Which is will be a important step for the renewable energy. If successful, in a few years a common person will be ready to produce solar thermoelectricity at home with the double benefit of producing electricity and hot steam. The paper presents a design methodology and heat transfer calculation for an concentrating system based on the Linear Fresnel Reflector (LFR) concept. The basic absorber design is an trapezoidal inverted air cavity without glass cover. The absorber is covered with a selective surface and is oriented north- south. This arrangement has shown good optical and thermal performance results validated by measurements during outdoor tests.

Valtchev, {Stanimir Stoyanov}, and DEE Group Author. "Survey on EV electrical drive train with induction motor." International Symposium on Electric Vehicles. 2012. 1-5. Abstract

In the last time many research works were devoted to the electrical drive train with induction motors due to its robust construction and low cost in comparison with its competitor, PM synchronous motor. The construction of the induction motor is simple but its efficient control needs more sophisticated algorithms and appropriate inverters in order to obtain the highest technical and economical performance. In this paper we present a review of the last research results on the induction motor topologies dedicated to EV, on the architecture of inverters and of the efficient control strategies. There will be presented many promising solutions which are analysed and compared in order to offer to the EV electrical drive train designers the necessary information for a selection to be done.

Delgado, Nuno, and Hervé Paulino. "Sobre um Mecanismo de Controlo de Concorrência baseado em Grupos de Recursos." INForum 2012 - Atas do 4º Simpósio de Informática. Eds. Antónia Lopes, and José Orlando Pereira. Universidade Nova de Lisboa, 2012. 302-305. Abstract
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Micaelo, Rui, André Santos, and Cátia Duarte Compaction and mixing temperatures of asphalt mixtures with modified bitumen. 5th Congress Eurasphalt & Eurobitume 2012. Istanbul, Turkey, 2012.
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.

Guirgis, Bassem, Cláudia Sá e Cunha, Inês Gomes, Miguel Cavadas, Isabel Silva, Gonçalo Doria, Gregory Blatch, Pedro Baptista, Eulália Pereira, Hassan Azzazy, Maria Mota, Miguel Prudêncio, and Ricardo Franco. "Gold nanoparticle-based fluorescence immunoassay for malaria antigen detection." Analytical and Bioanalytical Chemistry. 402.3 (2012): 1019-1027.
Azevedo, S. G., H. Carvalho, S. Duarte, and V. Cruz-Machado. "Influence of Green and Lean Upstream Supply Chain Management Practices on Business Sustainability." Engineering Management, IEEE Transactions on. 59 (2012): 1-13. AbstractWebsite

Green and lean paradigms have been adopted by companies in order to manage their relationships with suppliers in a supply chain management context, but nearly always separately and with little understanding of their influence on company performance. This paper proposes a theoretical framework for the analysis of the influence of green and lean upstream supply chain management practices on the sustainable development of businesses. To attend this objective, a set of performance measures covering economic (operational cost, environmental cost, and inventory cost), environmental (business wastage, green image, and CO2 emission), and social (corruption risk, supplier screening and local supplier) perspectives is proposed. An explanatory case study was conducted at a Portuguese automaker to test qualitatively the validity of the proposed theoretical framework. From the case study, a model is suggested, which encompasses the relationships between green and lean upstream supply chain practices and sustainable business development.

Rebelo, M., T. Diogo, and S. McKee. "A Mathematical Treatment of the Fluorescence Capillary-Fill Device." SIAM, J. Applied Mathematics. 72.4 (2012): 1081-1112.
Dimitrova, I., Vítor H. Fernandes, and J. Koppitz. "The maximal subsemigroups of semigroups of transformations preserving or reversing the orientation on a finite chain." Publicationes Mathematicae Debrecen. 81.1-2 (2012): 11-29.
Mouquinho, AI, K. T. Petrova, M. T. Barros, and J. C. Sotomayor. "New Polymer Networks for PDLC Films Application." New Polymers for Special Applications . Ed. A. De-Souza-Gomes. Rijeka: InTech, 2012. 139-164.
Pimenta, J., FMV Dias, C. C. Marques, M. C. Baptista, M. I. Vasques, A. E. M. Horta, J. P. Barbas, R. Soares, P. Mesquita, E. Cabrita, CMGA Fontes, J. A. Prates, and R. M. Pereira. "The Prion-like Protein Doppel Enhances Ovine Spermatozoa Fertilizing Ability." Reproduction in Domestic Animals. 47.2 (2012): 196-202. Abstract

The function of prion-like protein Doppel was suggested to be related to male fertility. In this study, the importance of ovine Doppel polypeptide on spermatozoa capacitation and fertilization was evaluated. After refolding, recombinant Doppel (rDpl) was supplemented with different concentrations (40, 80 or 190 ng/ml) to ovine spermatozoa during the capacitation process. In experiment 1, post-thawed ovine spermatozoa were incubated with different concentrations of rDpl during 1 h for swim-up, and changes in sperm motility, concentration, vigour, viability and capacitation were monitored (10 replicates). In experiment 2, the fertilization ability of post-swim-up spermatozoa incubated as above was tested through heterologous fertilization of bovine in vitro matured oocytes (n = 423, three replicates). Regardless of dosage, rDpl improved (p = 0.03) spermatozoa viability. Sperm individual motility and vigour were the highest (p = 0.04) for the group receiving 190 ng/ml rDpl. Sperm supplemented with the highest doses of rDpl achieved higher (p = 0.02) fertilization rates (56.0 +/- 3.0%) than control (39.1 +/- 2.2%) and 40 ng/ml rDpl (39.8 +/- 2.7%). Preliminary data suggest that Doppel protein may enhance in vitro spermatozoa fertilizing ability.

Rybarczyk, Y., Hoppenot P., Colle E., and Mestre D. "Sensori-motor appropriation of an artefact: a neuroscientific approach." Human Machine Interaction - Getting Closer. Ed. Maurtua Inaki. Rijeka: InTech, 2012. 187-212.copy.pdf
Sousa, Ana M. M., Simone Morais, Maria H. Abreu, Rui Pereira, Isabel Sousa-Pinto, Eurico J. Cabrita, Cristina Delerue-Matos, and Maria Pilar Gonca̧lves. "Structural, Physical, and Chemical Modifications Induced by Microwave Heating on Native Agar-like Galactans." Jornal of Agricultural and Food Chemistry . 60 (2012): 4977-4985. Abstract

Native agars from Gracilaria vermiculophylla produced in sustainable aquaculture systems (IMTA) were extracted under conventional (TWE) and microwave (MAE) heating. The optimal extracts from both processes were compared in terms of their properties. The agars’ structure was further investigated through Fourier transform infrared and NMR spectroscopy. Both samples showed a regular structure with an identical backbone, β-D-galactose (G) and 3,6-anhydro-α-L-galactose (LA) units; a considerable degree of methylation was found at C6 of the G units and, to a lesser extent, at C2 of the LA residues. The methylation degree in the G units was lower for MAEopt agar; the sulfate content was also reduced. MAE led to higher agar recoveries with drastic extraction time and solvent volume reductions. Two times lower values of [η] and Mv obtained for the MAEopt sample indicate substantial depolymerization of the polysaccharide backbone; this was reflected in its gelling properties; yet it was clearly appropriate for commercial application in soft-texture food products.

Pinto, R. M., A. A. Dias, M. Coreano, M. de Simone, B. M. Giuliano, J. P. Santos, and M. L. Costa. "Tautomerism in 5-aminotetrazole investigated by core-level photoelectron spectroscopy and ΔSCF calculations." J. Electron. Spectrosc. Related Phenomena. 185 (2012): 13-17. AbstractWebsite

The C 1s and N 1s photoelectron spectra of gas-phase 5-aminotetrazole (5ATZ) were recorded using synchrotron radiation, with the aim of evaluating 1H/2H tautomer population ratios. The core-electron binding energies (CEBEs) were estimated from computational results, using the delta self-consistent-field (ΔSCF) approach. Simulated spectra were generated using these CEBEs and the results from Gaussian-n (Gn, n=1, 2 and 3) and Complete Basis Set (CBS-4M and CBS-Q) methods. Results reveal the almost exclusive predominance of the 2H-tautomer, with a 1H/2H ratio of ca. 0.12/0.88, taken from a gross analysis of the XPS C 1s spectrum, recorded at 365 K.

Carvalho, T., V. Augusto, A. R. Brás, N. M. T. Lourenço, CAM Afonso, S. Barreiros, N. T. Correia, P. Vidinha, E. J. Cabrita, M. Dionísio, and B. Roling. "Understanding the Ion Jelly Conductivity Mechanism." Journal of Physical Chemistry B. 116 (2012): 2664-2676. Abstract

The properties of the light flexible device, ion jelly, which combines gelatin with an ionic liquid (IL) were recently reported being promising to develop safe and highly conductive electrolytes. This article aims for the understanding of the ion jelly conductive mechanism using dielectric relaxation spectroscopy (DRS) in the frequency range 10−1−106 Hz; the study was complemented with differential scanning calorimetry (DSC) and pulse field gradient nuclear magnetic resonance (PFG NMR) spectroscopy. The room temperature ionic liquid 1-butyl-3-methylimmidazolium dicyanamide (BMIMDCA) used as received (1.9% w/w water content) and with 6.6% (w/w) of water content and two ion jellies with two different ratios BMIMDCA/gelatin/water % (w/w), IJ1 (41.1/46.7/12.2) and IJ3 (67.8/25.6/6.6), have been characterized. A glass transition was detected by DSC for all materials allowing for classifying them as glass formers. For the ionic liquid, it was observed that the glass transition temperature decreases with the increase of water content. While in subsequent calorimetric runs crystallization was observed for BMIMDCA with negligible water content, no crystallization was detected for any of the ion jelly materials upon themal cycling. To the dielectric spectra of all tested materials, both dipolar relaxation and conductivity contribute; at the lowest frequencies, electrode and interfacial polarization highly dominate. Conductivity, which manifests much more intensity relative to dipolar reorientations, strongly evidences subdiffusive ion dynamics at high frequencies. From dielectric measures, transport properties as mobility and diffusion coefficients were extracted. Data treatment was carried out in order to deconvolute the average diffusion coefficients estimated from dielectric data in its individual contributions of cations (D+) and anions (D−). The D+ values thus obtained for IJ3, the ion jelly with the highest IL/gelatin ratio, cover a large temperature range up to room temperature and revealed excellent agreement with direct measurements from PFG NMR, obeying to the same VFT equation. For BMIMDCA6.6%water, which has the same water amount as IJ3, the diffusion coefficients were only estimated from DRS measurements over a limited temperature range; however, a single VFT equation describes both DRS and PFG NMR data. Moreover, it was found that the diffusion coefficients and mobility are similar for the ionic liquid and IJ3, which points to a role of both water and gelatin weakening the contact ion pair, facilitating the translational motion of ions and promoting its dissociation; nevertheless, it is conceivable that a critical composition of gelatin that leads to those properties. The VFT temperature dependence observed for the conductivity was found to be determined by a similar dependence of the mobility. Both conductivity and segmental motion revealed to be correlated as inferred by the relatively low values of the decoupling indexes. The obtained results show that ion jelly could be in fact a very promising material to design novel electrolytes for different electrochemical devices, having a performance close to the IL but presenting an additional stability regarding electrical measurements and resistance against crystallization relative to the bulk ionic liquid.

Barbosa, Rui, Diogo Dias, Nuno Lapa, and Benilde Mendes. "Using biomass ashes in concretes exposed to salted water and freshwater: mechanical and chemical properties." Advanced Materials Research. 587 (2012): 16-20. AbstractWebsite

The main aim of this work was to assess the possibility of using biomass ashes as substitutes for cement and natural aggregates in concretes without compromising their mechanical and chemical properties. Thirteen concrete formulations were prepared with different percentages of bottom and fly ashes produced at a forest biomass power plant. These formulations were submitted to mechanical compressive strength assays, after 28, 60 and 90 days of maturation. The reference formulation F1 that was produced without biomass ashes and one formulation incorporating fly and bottom ashes, F4, were selected for further characterization. After 90 days of maturation, the selected formulations were submitted to the leaching test described in the European Standard EN12457-2 (L/S ratio of 10 L/kg, in a batch extraction cycle of 24h) by using two different leaching agents: a synthetic marine medium (ASPM medium) and a synthetic freshwater medium (ISO 6341 medium). The eluates produced were submitted to chemical characterization which comprised a set of metals (As, Sb, Se, Cu, Zn, Ba, Hg, Cd, Mo, Pb, Ni, Cr, Cr VI, Al, Fe, Mg, Na, K and Ca), pH, SO42-, F-, dissolved organic carbon, chlorides, phenolic compounds and total dissolved solids. The substitution of 10% cement by fly ashes has not promoted the reduction of the compressive strength of concrete. The new formulation F4 has presented emission levels of chemical species similar or even lower to those observed for the reference formulation F1.