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2012
Cunha, Jácome, João Paulo Fernandes, Jorge Mendes, and João Saraiva. "Towards an Evaluation of Bidirectional Model-driven Spreadsheets." User evaluation for Software Engineering Researchers. USER' 12. ACM Digital Library, 2012. 25-28. Abstractuser12.pdf

Spreadsheets are widely recognized as popular programming systems with a huge number of spreadsheets being created every day. Also, spreadsheets are often used in the decision processes of profit-oriented companies. While this illustrates their practical importance, studies have shown that up to 90% of real-world spreadsheets contain errors. In order to improve the productivity of spreadsheet end-users, the software engineering community has proposed to employ model-driven approaches to spreadsheet development. In this paper we describe the evaluation of a bidirectional model-driven spreadsheet environment. In this environment, models and data instances are kept in conformity, even after an update on any of these artifacts. We describe the issues of an empirical study we plan to conduct, based on our previous experience with end-user studies. Our goal is to assess if this model-driven spreadsheet development framework does in fact contribute to improve the productivity of spreadsheet users.

Correia, Isabel, Teresa Melo, and Francisco Saldanha-da-Gama. "A two-echelon facility location problem with layout selection." Mathematics and Computers in Science and Engineering 3. 2012. Abstract

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Gião, R., V. Lúcio, C. Chastre, and A. Bras UFRG – Unidirectional fibre reinforced grout as strengthening material for reinforced concrete structures. BEFIB2012 – Fibre reinforced concrete. Guimarães: UMinho, 2012. Abstract

The present study is part of an extensive research project, where the main objective is to evaluate a strengthening solution for reinforced concrete structures using a small thickness jacketing in the compression side of the RC element with unidirectional fiber reinforced grout - UFRG.
For this purpose a high performance cementitious grout reinforced with continuous and unidirectional non woven fibermat has been developed. It was expected that the use of these type of fibers allowed an optimization of its percentage and orientation. It was expected that the use of these type of fibers allowed an optimization of its percentage and orientation. Besides, for continuous fibers (with an aspect ratio, defined as the length-to-diameter ratio, l/d=∞), the composite should attain higher tensile strength since the fiber embedment length is enough to prevent fiber pullout.
The experimental campaign included a set of preliminary tests that allowed the design of the fiber reinforced grout, sustained with rheological parameters [7] and mechanical characterization tests of the materials.
Finally, an experimental campaign was carried out in order to proceed to the mechanical characterization of the unidirectional fiber reinforced grout. Compressive tests were conducted in small thickness tubular specimens that enable the determination of the compressive strength and the static modulus of elasticity of the material. The tensile strength of the material was obtained using splitting tests of cubic specimens (according the standard DIN 1048-5). The experimental results are presented and analyzed.

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.

Coito, Fernando, Helena Fino, and Pedro Pereira. "Variability-Aware Optimization of RF Integrated Inductors in Nanometer-Scale Technologies." Integrated Circuits for Analog Signal Processing. New York: Springer-Verlag , 2012.
Contreras, Javier, Luis Gomes, Sergej Filonovich, Nuno Correia, Elvira Fortunato, Rodrigo Martins, and Isabel Ferreira. "3D scanning characteristics of an amorphous silicon position sensitive detector array system." Optics express. 20.4 (2012): 4583-4602. Abstract
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Contreras, J.a, Gomes Filonovich Correia Fortunato Martins Ferreira L. b S. a. "3D scanning characteristics of an amorphous silicon position sensitive detector array system." Optics Express. 20 (2012): 4583-4602. AbstractWebsite

The 3D scanning electro-optical characteristics of a data acquisition prototype system integrating a 32 linear array of 1D amorphous silicon position sensitive detectors (PSD) were analyzed. The system was mounted on a platform for imaging 3D objects using the triangulation principle with a sheet-of-light laser. New obtained results reveal a minimum possible gap or simulated defect detection of approximately 350 μm. Furthermore, a first study of the angle for 3D scanning was also performed, allowing for a broad range of angles to be used in the process. The relationship between the scanning angle of the incident light onto the object and the image displacement distance on the sensor was determined for the first time in this system setup. Rendering of 3D object profiles was performed at a significantly higher number of frames than in the past and was possible for an incident light angle range of 15 ° to 85 °. © 2012 Optical Society of America.

Chumakov, Yu, S. - Y. Xiong, JR Santos, I. Ferreira, K. Termentzidis, A. Pokropivny, P. Cortona, and S. Volz. "Ab Initio Calculations and Measurements of Thermoelectric Properties of V2O5 Films." Journal of Electronic Materials (2012): 1-7. Abstract
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Lucena, C., L. Palma, Alberto Cardoso, and P. Gil. "Adaptive Quasi-Optimal Gains Tuning of PI-Fuzzy Controllers." MED2012 - 20th Mediterranean Conference on Control and Automation. n/a 2012. Abstract
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Carvalho, H., S. G. Azevedo, and V. Cruz-Machado. "Agile and resilient approaches to supply chain management: influence on performance and competitiveness." Logistics Research. 4 (2012): 49-62. AbstractWebsite

Supply chain management must adopt different and more innovative strategies that support a better response to customer needs in an uncertain environment. Supply chains must be more agile and be more capable of coping with disturbances, meaning that supply chains must be more resilient. The simultaneous deployment of agile and resilient approaches will enhance supply chain performance and competitiveness. Accordingly, the main objective of this paper is to propose a conceptual framework for the analysis of relationships between agile and resilient approaches, supply chain competitiveness and performance. Operational and economic performance measures are proposed to facilitate the monitoring of the influence of these practices on supply chain performance. The influence of the proposed agile and resilient practices on supply chain competitiveness is also examined in terms of time to market, product quality and customer service.

Neves, Nuno, Raquel Barros, Elsa Antunes, João Calado, Elvira Fortunato, Rodrigo Martins, and Isabel Ferreira. "Aluminum doped zinc oxide sputtering targets obtained from nanostructured powders: Processing and application." Journal of the European Ceramic Society (2012). Abstract
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Contreras, Javier, Marek Idzikowski, Sónia Pereira, Sergej A. Filonovich, Elvira Fortunato, Rodrigo Martins, and Isabel Ferreira. "Amorphous Silicon Position Sensitive Detector Array for Fast 3-D Object Profiling." Sensors Journal, IEEE. 12.4 (2012): 812-820. Abstract
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Contreras, J.a, Idzikowski Pereira Filonovich Fortunato Martins Ferreira M. b S. a. "Amorphous silicon position sensitive detector array for fast 3-d object profiling." IEEE Sensors Journal. 12 (2012): 812-820. AbstractWebsite

A 32/128 linear array of 1-D amorphous silicon position sensitive detectors (PSD) was integrated into a self constructed suitable and portable data acquisition prototype system. The system is comprised by a commercially available existing electronics module suitable for photodiode data acquisition operations and by another adapter module, which allows for removal and replacement of the 32/128 PSD based sensor. This system is applied for imaging 3-D objects using the triangulation principle with a sheet-of-light laser. The sensor array response obtained from the reflected light of the object was fed into an electronic readout system and the corresponding signals were analyzed using the relevant data algorithm. The obtained results show a sensor nonlinearity of about 4%-7%, a wide sensor/system dynamic range and a 3-D profile spatial resolution supplied by each sensor strip of 339 μm, which can easily be reduced to 8.5 μm and even further with appropriate software modifications. © 2011 IEEE.

Moutinho, Filipe, Lu{\'ı}s Gomes, Anikó Costa, and Jose Pimenta. "Asynchronous wrappers configuration within {GALS} systems specified by Petri nets." 21st {IEEE} International Symposium on Industrial Electronics, {ISIE} 2012, Hangzhou, China, 28-31 May, 2012. 2012. 1357-1362. Abstract
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Carvalho, J., L. B. Oliveira, JP Oliveira, J. Goes, and M. M. Silva. "A balun transimpedance amplifier with adjustable gain for integrated SPO< inf> 2 optic sensors." Mixed Design of Integrated Circuits and Systems (MIXDES), 2012 Proceedings of the 19th International Conference. IEEE, 2012. 178-182. Abstract
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Marques, Filipe J., and Carlos A. Coelho. "The block sphericity test." Mathematical Methods in the Applied Sciences. 35 (2012): 373-383. Abstract
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Graham, Lisa M., Vandana Gupta, Georgia Schafer, Delyth M. Reid, Matti Kimberg, Kevin M. Dennehy, William G. Hornsell, Reto Guler, Maria A. Campanero-Rhodes, Angelina S. Palma, Ten Feizi, Stella K. Kim, Peter Sobieszczuk, Janet A. Willment, and Gordon D. Brown. "The C-type Lectin Receptor CLECSF8 (CLEC4D) Is Expressed by Myeloid Cells and Triggers Cellular Activation through Syk Kinase." Journal of Biological Chemistry. 287 (2012): 25964-25974. Abstract
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Cerdeira, J. O., M. J. Martins, and P. C. Silva. "A Combinatorial Approach to Assess the Separability of Clusters." Journal of Classification. 29 (2012): 7-22. Abstract
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Cardoso, Alberto, M. T. Restivo, P. Cioga, M. Delgado, J. N. Monsanto, J. Bicker, E. Nunes, and P. Gil. "Demonstration of Online Educational Modules with Online Experiments." REV2012 - Remote Engineering & Virtual Instrumentation. n/a 2012. Abstract
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Palma, L., F. Coito, and P. Gil. "Design of Adaptive Sliding Window PI-PCA Controller." 20th Mediterranean Conference on Control & Automation. n/a 2012. Abstract
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Palma, Angelina S., Yan Liu, Yibing Zhang, Hongtao Zhang, Ana S. Luis, Ana Luisa Carvalho, Harry J. Gilbert, Alisdair Boraston, Carlos M. G. A. Fontes, Wengang Chai, and Ten Feizi. "Designer-oligosaccharide microarrays to decipher ligands in mammalian and prokaryotic glucan-recognition systems." Glycobiology. 22 (2012): 1612-1613. Abstract
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Azevedo, S. G., K. Govindan, H. Carvalho, and V. Cruz-Machado. "Ecosilient Index to assess the greenness and resilience of the upstream automotive supply chain." Journal of Cleaner Production. in press (2012). AbstractWebsite

This paper suggests an Ecosilient Index to assess the greenness and resilience of automotive companies and the corresponding supply chain. An integrated assessment model is proposed based on green and resilient practices. The Delphi technique is used to obtain the weights of the supply chain paradigms that are the focus of the study and the corresponding practices. The application of the proposed index is then illustrated using a case study approach in the automotive supply chain; in particular the case study is focused in the link supplier/manufacturer. The case study findings confirm the applicability of this index in a real-world supply chain and highlight its managerial implications. The results show that the resilient paradigm is considered to be the one that contributes more to the competitiveness of the automotive supply chain. The green practice identified as the most important to the greenness of this industry is to reduce energy consumption. The significant contributions to resilience are sourcing strategies that allow switching of suppliers, flexible supply base/flexible sourcing and creating total supply chain visibility. The proposed index was developed in the context of automotive sector; this constitutes an initial effort to close the gap between theory and practice. Future research is needed to investigate the index applicability in different industry contexts.

Vinagre, C., D. Madeira, L. Narciso, H. N. Cabral, and M. S. Diniz. "Effect of handling, confinement and crowding in HSP70 production in Pachygrapsus marmoratus, a model species for climate change experiments." Journal of Sea Research. 72 (2012): 64-68. AbstractWebsite
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Vinagre, C., D. Madeira, L. Narciso, H. N. Cabral, and M. Diniz. "Effect of temperature on oxidative stress in fish: Lipid peroxidation and catalase activity in the muscle of juvenile seabass, Dicentrarchus labrax." Ecological Indicators. 23 (2012): 274-279. AbstractWebsite
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Cavalheiro, D., A. C. Silva, S. Valtchev, JP Teixeira, and V. Vassilenko. "Energy harvested from respiratory effort." BIODEVICES 2012 - Proceedings of the International Conference on Biomedical Electronics and Devices (2012): 388-392. Abstract
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