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2015
Barreto, J., D. Martins, Borges P. de Sousa, S. Kar, G. Bonfait, and I. Catarino Gas gap heat switch for a Cryogen-free magnet system., 2015.
Teixeira, João, Nuno Neuparth, Amalia Botelho, Ana Papoila, Pedro Martins, Paulo Paixão, Iolanda Caires, Daniel Aelenei, João Viegas, Manuela Cano, and Ana Mendes GERIA - Geria Study in Portugal on Health Effects of Air Quality in Elderly Care Centers. Eds. Jo Teixeira, Nuno Neuparth, Am Botelho, Ana Papoila, Pedro Martins, Paix, Iolanda Caires, Daniel Aelenei, Jo Viegas, Manuela Cano, and Ana Mendes. Published by Instituto de Sa: ISPUP - Instituto de Saúde Pública da Universidade do Porto, 2015. AbstractWebsite

As people have become increasingly aware, the age of the European population is rising and the percentage of adults aged 65 years and older is expected to increase. In addition, older people spend about 20 hours per day indoors, and many of them spend essentially their time in elderly care centers (ECC). In this sense, the study of indoor environments and how elder people may be particularly at risk of adverse health effects from pollutants, even at low exposures, due to multiple underlying chronic diseases is becoming an important issue to be addressed by research. Such conditions are highly prevalent, multifactorial, and associated with multiple comorbidities and poor outcomes, such as increased disability and decreased quality of life. The importance of this topic was heightened in 2012 by the World Health Day in 2012 Ageing and health with the theme "Good health adds life to years" and also the ?European Year for Active Ageing and Solidarity between Generations?. Accordingly, this project is suitable to integrate these initiatives and to ensure greater recognition of what older people bring to society and create more supportive conditions for them. To our knowledge, this is the first study in Portugal to assess effects of indoor air contaminants on health status and quality of life in older persons living in ECC. The aim of GERIA project is to carry out a risk assessment, often difficult for older people, involving the identification of multiple factors potentially affecting health and quality of life, the quantification of human exposure to pollutants, and the evaluation of the individual?s response to these stimuli. The results of this project contribute to the understanding of health effects due to indoor environment variables and to provide health benefits to ECC residents with relatively simple measures.

Campos, S., F. Viseu, H. Rocha, and J. A. Fernandes The graphing calculator in the promotion of mathematical writing. Proceedings of 12th International Conference onTechnology in Mathematics Teaching. Faro, Portugal: Universidade do Algarve, 2015. Abstract

Through writing, students express many of their processes and ways of thinking. Since at high school level some of the activities are carried out with the graphing calculator, we intend to investigate the contribution of this resource to promote the mathematical writing in the learning of continuous nonlinear models at 11th grade. Adopting a qualitative methodology, we collected and analyzed the students’ writing productions. What they write when using the calculator gives evidence about the information valued (when they sketch graphics without any justification); about the strategies used (when they define the viewing window and relate different menus on the graphing calculator); and about the reasoning developed (when they justify the information given by the calculator and the formulation of generalizations and conjectures validation).

Mota, Bruna, Ana Carvalho, Maria Isabel Gomes, and Ana Paula Barbosa-povoa Green Supply Chain Design and Planning. Eds. J. M. Framinan, P. Perez Gonzalez, and A. Artiba. Proceedings of 2015 International Conference on Industrial Engineering and Systems Management (IESM),. I4 e2 - M. Goudalier, 2015. Abstract2015_motacarvalhogomesbpovoa_iesm2015.pdf

A Mixed Integer Linear Programming model for the design and planning of green supply chains is developed. Strategic and tactical decisions are taken, namely on facility location and capacity installation, supplier selection, technology selection, transportation network definition, supply planning, and product recovery. The aim of this work is to study the use of environmental indicators in these decisions while accounting for profit objectives. Different objective functions concerning environmental aspects are implemented. ReCiPe quantifies the environmental performance of the supply chain and combinations of ReCiPe’s midpoint categories allow a deeper analysis of the impact of these categories in strategic and tactical decisions. The goal is to understand if focusing on selected categories affects supply chain decisions and overall supply chain environmental impact. Net Present Value quantifies the economic performance and is used for lexicographic optimization. The model is applied to a case-study and important managerial insights are obtained. From a holistic point of view, it answers the question: how should supply chain environmental impact be assessed? From a case-study perspective, insights are obtained regarding what type of improvements should be implemented to reduce the environmental impact and how this would affect supply chain strategic and tactical decisions, along with economic performance.

Couto, Marco, Jácome Cunha, and João Paulo Fernandes. "GreenDroid: A Tool for Analysing Power Consumption in the Android Ecosystem." Proceedings of the 13th International Conference Informatics’2015. Propad, Slovakia 2015. 73-78.informatics2015.pdf
Cardoso, Tiago, João Delgado, and José Barata. "Hand gesture recognition towards enhancing accessibility." Procedia Computer Science. 67 (2015): 419-429. Abstract

Human-Computer-Interaction (HCI) is a key topic on the Accessibility area, namely in what concerns a Smart-City environment, where humans have to interact with artefacts spread all around one particular city. In the last decade HCI has experienced a significant evolution towards a desired fully natural user interface, for example in what concerns the ability to recognize a wide range of hand gestures in real-time. Some efforts have lately been made in the hardware sector in order to deploy sensors that may gather information about the human body movements, as detailed as possible. One example of this effort is the Kinect Sensor from Microsoft. Nevertheless, although these solutions provide a solution for the body movement, they lack on the details, namely the hands, given their small dimension compared to the body as a whole. In other words, the SDKs provided by the vendors of these devices usually lack on the needed details concerning hand movements that would be needed for an accurate hand gesture recognition implementation. This paper presents an extension to the Kinect SDK based on a contour analysis for the estimation of the hand position. This algorithms are then used to provide the creation of a gesture library that might be used afterwards.

Koerber, H., J. Xavier, P. P. Camanho, Y. E. Essa, and Martín F. de la Escalera. "High strain rate behaviour of 5-harness-satin weave fabric carbon-epoxy composite under compression and combined compression-shear loading." International Journal of Solids and Structures. 54 (2015): 172-182. AbstractWebsite

Abstract The strain rate dependent mechanical behaviour was studied for the common out-of-autoclave aerospace textile composite 5-harness-satin carbon�epoxy. End-loaded 15 � , 30 � and 45 � off-axis and 90 � compression tests were carried out at three different strain rate levels ( 4 � 10 - 4 s - 1 , 200 s - 1 and 1000 s - 1 ) to determine the effect of strain rate for transverse compression and combined transverse compression/in-plane shear loading. The dynamic tests were carried out on a split-Hopkinson pressure bar, where high speed photography and digital image correlation allowed a detailed study of the specimen deformation and failure process. Quasi-static reference tests were carried out on an electro-mechanical test machine using the same specimen type and a static \{DIC\} system. Pronounced strain rate effects on the axial stress�strain response were observed for all specimen types. Failure envelopes for the combined s 22 c - t 12 stress state were derived from the experimental data and compared with the maximum stress criterion, which appears well suited to approximate the experimental failure envelope at all strain rate levels. It was observed that the failure envelope was simply scaled up with increasing strain rate, while the overall shape was found to be strain rate independent.

Maiti, B. K., L. B. Maia, C. M. Silveira, S. Todorovic, C. Carreira, M. S. Carepo, R. Grazina, I. Moura, S. R. Pauleta, and JJG Moura. "Incorporation of molybdenum in rubredoxin: models for mononuclear molybdenum enzymes." Journal of Biological Inorganic Chemistry. 20 (2015): 821-829. AbstractWebsite
Tolstogouzov, A. B., S. F. Belykh, V. S. Gurov, A. A. Lozovan, A. I. Taganov, O. M. N. D. Teodoro, A. A. Trubitsyn, and S. P. Chenakin. "Ion Beam Sources Based on Room Temperature Ionic Liquids for Aerospace Applications , Nanotechnology , and Microprobe Analysis ( Review )." Instruments and Experimental Techniques. 58.1 (2015): 1-14.2014_review_ion_beam_sources.pdf
Govindan, K., Azevedo, S. G., Carvalho, H., and V. and Cruz Machado. "Lean, green and resilient practices influence on supply chain performance: interpretive structural modeling approach." International Journal of Environmental Science and Technology. 12 (2015): 15-34.
Catarino, I., D. Martins, and R. Sudiwala Materials for damping the PTC-induced thermal fluctuations of the cold-head. Cryogenic Engineering Conference and the Cryogenic Materials Conference . Tucson, AZ, USA, 2015.
Catalanotti, G., and J. Xavier. "Measurement of the mode II intralaminar fracture toughness and R-curve of polymer composites using a modified Iosipescu specimen and the size effect law." Engineering Fracture Mechanics. 138 (2015): 202-214. AbstractWebsite

Abstract A modified Iosipescu specimen is proposed to measure the mode İI\} intralaminar fracture toughness and the corresponding crack resistance curve of fibre reinforced composites. Due to the impossibility of scaling the specimen, a modification of the classical size effect method is proposed. The calculation of the crack driving force curves is performed using the Finite Element Method. The classical Iosipescu shear feature was used and tests were coupled with digital image correlation to support the proposed approach. Experiments were performed on IM7/8552 material system and the R-curve was obtained. The steady-state value of the fracture toughness of the ply is found to be equal to R 0 ss = 34.4  kJ/m2.

Gomes, Luís, Miguel Santos, Thiago Pereira, and Anikó Costa. "Model-Based Development of an Autonomous Sailing Yacht Controller." 2015 {IEEE} International Conference on Autonomous Robot Systems and Competitions, {ICARSC} 2015, Vila Real, Portugal, April 8-10, 2015. 2015. 103-108. Abstract

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Viegas, João Carlos, Susana Nogueira, Daniel Aelenei, Hildebrando Cruz, Manuela Cano, and Nuno Neuparth. "Numerical evaluation of ventilation performance in children day care centres." Building Simulation. 8 (2015): 189-209. Abstract

Modelling of ventilation is strongly dependent on the physical characteristics of the building of which precise evaluation is a complex and time consuming task. In the frame of a research project, two children day care centres (CDCC) have been selected in order to measure the envelope air permeability, the flow rate of mechanical ventilation systems and indoor and outdoor temperature. The data obtained was used as input to the computer code CONTAM for ventilation simulations. The results obtained were compared with direct measurements of ventilation flow from short term measurements with CO2 tracer gas and medium term measurements with perfluorocarbon tracer (PFT) gas decay method. After validation, in order to analyse the main parameters that affect ventilation, the model was used to predict the ventilation rates for a wide range of conditions. The purpose of this assessment was to find the best practices to improve natural ventilation. A simple analytical method to predict the ventilation flow rate of rooms is also presented. The method is based on the estimation of wind effect on the room through the evaluation of an average factor and on the assessment of relevant cross section of gaps and openings combined in series or in parallel. It is shown that it may be applied with acceptable accuracy for this type of buildings when ventilation is due essentially to wind action.

Biscaia, Hugo C., Carlos Chastre, André Viegas, and Noel Franco. "Numerical modelling of the effects of elevated service temperatures on the debonding process of frp-to-concrete bonded joints." Composites Part B: Engineering. 70 (2015): 64-79. AbstractWebsite

There are many issues concerning the performance behaviour of FRP-to-concrete interfaces at elevated service temperatures (EST). At EST, i.e. slightly above the glass transition temperature (Tg), some properties associated with the FRP composites, such as the stiffness, strength or the bond characteristics, degrade. This is a crucial issue and there are only a few studies that take into account such effects on FRP-to-concrete interfaces at EST. This paper examines, through a numerical analysis, the performance of FRP-to-concrete bonded joints at EST using a new discrete model based on truss elements and shear springs. The External Bonded Reinforcement (EBR) systems subjected to EST are analyzed. The numerical discrete model was implemented in a MATLAB routine and the bond-slip curves of the interfaces at EST were obtained from a model found in literature. The numerical results revealed that the interface at EST behaves similarly to one with two equal mechanical loads applied at both ends of the FRP plate. The load-slip curves or bond stresses, strains or slippages along the bonded length obtained from several bond-slip curves at different temperatures were obtained. Two different single-lap shear tests were simulated at steady-state (steady temperature followed by load increase) and transient state (steady load followed by temperature increase). Regarding the influence of the temperature on the adhesion between the FRP and concrete, the results showed that an increase in the temperature at an earlier situation, i.e. during a period where temperature had no influence in the concrete deformations, leads to an increase in the effective bond length of the interface affecting the initial strength of the interface.

Marques, Filipe J., Carlos A. Coelho, and Miguel de Carvalho. "On the distribution of linear combinations of independent Gumbel random variables (Supplementary Material)." Statistics and Computing. 25 (2015): 1-5. Abstract

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Cicalò, Serena, Vítor H. Fernandes, and Csaba Schneider. "Partial transformation monoids preserving a uniform partition." Semigroup Forum (DOI 10.1007/s00233-014-9629-5). 90.2 (2015): 532-544. AbstractWebsite

The objective of this paper is to study the monoid of all partial
transformations of a finite set that preserve a uniform partition. In addition
to proving that this monoid is a quotient of a wreath product with respect to a
congruence relation, we show that it is generated by 5 generators, we compute
its order and determine a presentation on a minimal generating set.

Passos, Fabio, Mouna Kotti, R. Gonzalez-Echevarria, M. H. Fino, E. Roca, R. Castro-Lopez, and F. V. Fernandez Physical vs. Surrogate Models of Passive RF Devices. 2015 IEEE International Symposium on Circuits and Systems. Lisbon: IEEE, 2015.
Cavique, Miguel, João Flores, Miguel Amado, António Gonçalves-Coelho, and António Mourão. "A preliminary check of the refurbishing large office buildings to a zero energy condition." CIRP. 1.34 (2015): 193-198.
Coelho, Helena, T. Matsushita, G. Artigas, H. Hinou, FJ Cañada, R. Lo-Man, C. Leclerc, E. J. Cabrita, J. Jiménez-Barbero, S. - I. Nishimura, F. Garcia-Martín, and F. Marcelo. "The Quest for Anticancer Vaccines: Deciphering the Fine-Epitope Specificity of Cancer-Related Monoclonal Antibodies by Combining Microarray Screening and Saturation Transfer Difference NMR." J. Am. Chem. Soc.. 137 (2015): 12438-12441.
Corvo, Marta C., João Sardinha, Teresa Casimiro, Graciane Marin, Marcus Seferin, Sandra Einloft, Sonia C. Menezes, Jairton Dupont, and Eurico J. Cabrita. "A rational approach to sustainable CO2-capture by imidazolium ionic liquids: tuning CO2 solubility by cation alkyl branching." Chem. Sus. Chem.. 8 (2015): 1935-1946.
Aquino, Aline S., FL Bernard, JV Borges, Luis Mafra, Felipe Dalla Vecchia, MO Vieira, R. Ligabue, VV Chaban, E. J. Cabrita, and S. Einloft. "Rationalizing the role of the anion in CO2 capture and conversion using imidazolium-based ionic liquid modified mesoporous sílica." RSC Advances. 5 (2015): 64220-64227.
Crucho, C. I. C., P. Correia-da-Silva, K. T. Petrova, and M. T. Barros. "Recent progress in the field of glycoconjugates." Carbohydr. Res. 402 (2015): 124-132. DOI: 10.1016/j.carres.2014.10.005.
Cain, A. J., R. D. Gray, and A. Malheiro. "Rewriting systems and biautomatic structures for Chinese, hypoplactic, and sylvester monoids." Int. J. Algebra Comput.. 25 (2015): 51-80. AbstractWebsite

This paper studies complete rewriting systems and biautomaticity for three interesting classes of finite-rank homogeneous monoids: Chinese monoids, hypoplactic monoids, and sylvester monoids. For Chinese monoids, we first give new presentations via finite complete rewriting systems, using more lucid constructions and proofs than those given independently by Chen & Qui and Güzel Karpuz; we then construct biautomatic structures. For hypoplactic monoids, we construct finite complete rewriting systems and biautomatic structures. For sylvester monoids, which are not finitely presented, we prove that the standard presentation is an infinite complete rewriting system, and construct biautomatic structures. Consequently, the monoid algebras corresponding to monoids of these classes are automaton algebras in the sense of Ufnarovskij.

Amarante dos Santos, Filipe, Corneliu Cismasiu, and Chiara Bedon. "Smart glazed cable façade subjected to a blast loading." Proceedings of the Institution of Civil Engineers-Structures and Buildings (2015): 1-10. Abstract

This paper investigates the dynamic behaviour of cable-supported glazing façades
subjected to medium-level air blast loads. Preliminary numerical studies are carried-out in
SAP2000 by means of a geometrically refined and simplified lumped-mass finite-element
numerical model, in order to assess the major effects of the design blast load in the main
façade components. As shown, both the glass panels and the cable system are able to
properly accommodate the incoming impulsive loads, typically involving extreme ...